Genetics of Breast and Ovarian Cancer (PDQ®): Genetics - Health Professional Information [NCI]

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Genetics of Breast and Ovarian Cancer

Purpose of This PDQ Summary

This PDQ cancer information summary for health professionals provides comprehensive, peer-reviewed, evidence-based information about the genetics of breast and ovarian cancer. This summary is reviewed regularly and updated as necessary by the Cancer Genetics Editorial Board.

The following information is included in this summary:

  • Family history and other risk factors for breast and ovarian cancer.
  • Models for predicting breast cancer risk.
  • Major genes associated with breast and ovarian cancer risk.
  • Screening and risk modification for hereditary breast and ovarian cancer.
  • Psychosocial issues associated with hereditary breast and ovarian cancer and genetic testing.

The summary also contains level-of-evidence designations. These designations are intended to help readers assess the strength of the evidence in relation to specific studies or strategies. A description of how level-of-evidence designations are made is described in detail in the PDQ summary Cancer Genetics Overview.

This summary is intended to provide clinicians a framework for discussing genetic testing, screening, and risk modification options with individuals at risk for hereditary breast and ovarian cancer, as well as for making referrals to cancer risk counseling services. It does not provide formal guidelines or recommendations for making health care decisions. Information in this summary should not be used as a basis for reimbursement determinations.

Introduction

General Information

Many of the medical and scientific terms used in this summary are found in the NCI Dictionary of Genetics Terms. When a linked term is clicked, the definition will appear in a separate window.

Many of the genes and conditions described in this summary are found in the Online Mendelian Inheritance in Man (OMIM) database. When OMIM appears after a gene name or the name of a condition, click on OMIM for a link to more information.

Among women, breast cancer is the most commonly diagnosed cancer after nonmelanoma skin cancer, and is the second leading cause of cancer deaths after lung cancer. In 2009, an estimated 194,280 new cases will be diagnosed, and 40,610 deaths from breast cancer will occur.[1] The incidence of breast cancer, particularly for estrogen receptor-positive cancers occurring after age 50 years, has declined at a faster rate since 2003; this may be temporally related to a decrease in hormone replacement therapy following early reports from the Women's Health Initiative.[2] Ovarian cancer is the ninth most common cancer, with an estimated 21,550 new cases in 2009, but is the fifth most deadly, with an estimated 14,600 deaths in 2009.[1] (Refer to the PDQ summary on Breast Cancer Treatment and Ovarian Epithelial Cancer Treatment for more information on breast cancer and ovarian cancer rates, diagnosis, and management.)

A possible genetic contribution to both breast and ovarian cancer risk is indicated by the increased incidence of these cancers among women with a family history (see the Family History as a Risk Factor for Breast Cancer and the Family History as a Risk Factor for Ovarian Cancer sections below), and by the observation of rare families in which multiple family members are affected with breast and/or ovarian cancer, in a pattern compatible with autosomal dominant inheritance of cancer susceptibility. Formal studies of families (linkage analysis) have subsequently proven the existence of autosomal dominant predispositions to breast and ovarian cancer and have led to the identification of several highly penetrantgenes as the cause of inherited cancer risk in many cancer-prone families. (Refer to the PDQ summary Cancer Genetics Overview for more information on linkage analysis.) Mutations in these genes are rare in the general population and are estimated to account for no more than 5% to 10% of breast and ovarian cancer cases overall. It is likely that other genetic factors contribute to the etiology of some of these cancers.

Family History as a Risk Factor for Breast Cancer

In cross-sectional studies of adult populations, 5% to 10% of women have a mother or sister with breast cancer, and about twice as many have either a first-degree relative or a second-degree relative with breast cancer.[3,4,5,6] The risk conferred by a family history of breast cancer has been assessed in both case-control and cohort studies, using volunteer and population-based samples, with generally consistent results.[7] In a pooled analysis of 38 studies, the relative risk (RR) of breast cancer conferred by a first-degree relative with breast cancer was 2.1 (95% confidence interval [CI], 2.0–2.2).[7] Risk increases with the number of affected relatives and age at diagnosis.[4,5,7] Refer to the Penetrance of Mutations section for a discussion of familial risk for women from families with BRCA1/2 mutations who themselves test negative for the family mutation.

Family History as a Risk Factor for Ovarian Cancer

Although reproductive, demographic, and lifestyle factors affect risk of ovarian cancer, the single greatest ovarian cancer risk factor is a family history of the disease. A large meta-analysis of 15 published studies estimated an odds ratio (OR) of 3.1 for the risk of ovarian cancer associated with at least one first-degree relative with ovarian cancer.[8]

Autosomal Dominant Inheritance of Breast/Ovarian Cancer Predisposition

Autosomal dominant inheritance of breast/ovarian cancer is characterized by transmission of cancer predisposition from generation to generation, through either the mother's or the father's side of the family, with the following characteristics:

  • Inheritance risk of 50%. When a parent carries an autosomal dominant genetic predisposition, each child has a 50:50 chance of inheriting the predisposition. Although the risk of inheriting the predisposition is 50%, not everyone with the predisposition will develop cancer because of incomplete penetrance and/or gender-restricted or gender-related expression.
  • Both males and females can inherit and transmit an autosomal dominant cancer predisposition. A male who inherits a cancer predisposition and shows no evidence of it can still pass the altered gene on to his sons and daughters.

Breast and ovarian cancer are components of several autosomal dominant cancer syndromes. The syndromes most strongly associated with both cancers are BRCA1 or BRCA2 mutation syndromes. Breast cancer is also a common feature of Li-Fraumeni syndrome due to TP53 mutations; of Cowden syndrome due to PTEN mutations; and with mutations in CHEK2.[9] Other genetic syndromes that may include breast cancer as an associated feature include heterozygous carriers of the ataxia telangiectasia (AT) gene and Peutz-Jeghers syndrome. Ovarian cancer has also been associated with Lynch syndrome, basal cell nevus (Gorlin) syndrome (OMIM), and multiple endocrine neoplasia type 1 (MEN1) (OMIM).[9] Mutations in each of these genes produce different clinical phenotypes of characteristic malignancies and, in some instances, associated nonmalignant abnormalities.

The family characteristics that suggest hereditary breast and ovarian cancer predisposition include the following:

  • Cancers typically occur at an earlier age than in sporadic cases (defined as cases not associated with genetic risk).
  • Two or more primary cancers in a single individual. These could be multiple primary cancers of the same type (e.g., bilateral breast cancer) or primary cancer of different types (e.g., breast and ovarian cancer in the same individual).
  • Cases of male breast cancer.
  • Possible increased risk of other selected cancers and benign features for males and females. (Refer to the Major Genes section of this summary for more information.)

There are no pathognomonic features distinguishing breast and ovarian cancers occurring in BRCA1 or BRCA2 mutation carriers with those occurring in noncarriers. Breast cancers occurring in BRCA1 mutation carriers are more likely to be estrogen receptor (ER)-negative, progesterone receptor (PR)-negative, and HER2/neu receptor-negative and have a basal phenotype. BRCA1-associated ovarian cancers are unlikely to be of mucinous or borderline histopathology. (Refer to the Pathology/Prognosis of Breast Cancer and Pathology/Prognosis of Ovarian Cancer sections for more information.)

Difficulties in Identifying a Family History of Breast and Ovarian Cancer Risk

When using family history to assess risk, the accuracy and completeness of family history data must be taken into account. A reported family history may be erroneous, or a person may be unaware of relatives affected with cancer. In addition, small family sizes and premature deaths may limit the information obtained from a family history. Breast or ovarian cancer on the paternal side of the family usually involves more distant relatives than on the maternal side and thus may be more difficult to obtain. When comparing self-reported information with independently verified cases, the sensitivity of a history of breast cancer is relatively high, at 83% to 97%, but lower for ovarian cancer, at 60%.[10,11]

Other Risk Factors for Breast Cancer

Other risk factors for breast cancer include age, reproductive and menstrual history, hormone therapy, radiation exposure, mammographic breast density, alcohol intake, physical activity, anthropometric variables, and a history of benign breast disease. (Refer to the PDQ summary on Breast Cancer Prevention for more information.) These factors are considered in more detail in numerous reviews,[12,13] including among BRCA1/BRCA2 mutation carriers.[14] Brief summaries are given below, highlighting, where possible, the effect of these risk factors in women who are genetically susceptible to breast cancer. (More information about their effects in BRCA1/BRCA2 mutation carriers can be found in the section on Interventions later in this document.)

Age

Cumulative risk of breast cancer increases with age, with most breast cancers occurring after age 50 years.[15] In women with a genetic susceptibility, breast cancer, and to a lesser degree, ovarian cancer, tends to occur at an earlier age than in sporadic cases.

Reproductive and menstrual history

Breast cancer risk increases with early menarche and late menopause, and is reduced by early first full-term pregnancy. Although results have been complex and may be gene dependent, several studies have suggested that the influence of these factors on risk in BRCA1/BRCA2 mutation carriers appear to be similar to noncarriers.[14,16]

Oral contraceptives

Oral contraceptives may produce a slight increase in breast cancer risk among long-term users, but this appears to be a short-term effect. In a meta-analysis of data from 54 studies, the risk of breast cancer associated with oral contraceptive use did not vary according to a family history of breast cancer.[17]

Oral contraceptives are sometimes recommended for ovarian cancer prevention in BRCA1 and BRCA2 mutation carriers, but studies of their effect on breast cancer risk have been inconsistent.[18,19,20]

Hormone Replacement Therapy

Data exist from both observational and randomized clinical trials regarding the association between postmenopausal hormone replacement therapy (HRT) and breast cancer. A meta-analysis of data from 51 observational studies indicated a RR of breast cancer of 1.35 (95% CI, 1.21–1.49) for women who had used HRT for 5 or more years after menopause.[21] The Women's Health Initiative (WHI), a randomized controlled trial of about 160,000 postmenopausal women, investigated the risks and benefits of HRT. The estrogen-plus-progestin arm of the study, which randomized more than 16,000 women to receive combined HRT or placebo, was halted early because health risks exceeded benefits.[22,23] Adverse outcomes prompting closure included significant increase in both total (245 vs. 185 cases) and invasive (199 vs. 150 cases) breast cancers (RR = 1.24; 95% CI, 1.02–1.5, P<.001) and increased risks of coronary heart disease, stroke, and pulmonary embolism. Similar findings were seen in the estrogen-progestin arm of the prospective observational Million Women's Study in the United Kingdom.[24] The risk of breast cancer was not elevated, however, in women randomly assigned to estrogen-only versus placebo in the WHI study (RR = 0.77; 95% CI, 0.59–1.01). Eligibility for the estrogen-only arm of this study required hysterectomy, and 40% of these patients also had undergone oophorectomy, which potentially could have impacted breast cancer risk.[25]

The association between HRT and breast cancer risk among women with a family history of breast cancer has not been consistent; some studies suggest risk is particularly elevated among women with a family history, while others have not found evidence for an interaction between these factors.[26,27,28,29,30,21] The increased risk of breast cancer associated with HRT use in the large meta-analysis did not differ significantly between subjects with and without a family history. The WHI study has not reported analyses stratified on breast cancer family history, and subjects have not been systematically tested for BRCA1/2 mutations.[23] Short-term use of hormones for treatment of menopausal symptoms appears to confer little or no breast cancer risk.[21,31] The effect of HRT on breast cancer risk among carriers of BRCA1 or BRCA2 mutations has been studied only in the context of bilateral risk-reducing oophorectomy, in which short-term replacement does not appear to reduce the protective effect of oophorectomy on breast cancer risk.[32]

Radiation exposure

Observations in survivors of the atomic bombings of Hiroshima and Nagasaki and in women who have received therapeutic radiation treatments to the chest and upper body document increased breast cancer risk as a result of radiation exposure. The significance of this risk factor in women with a genetic susceptibility to breast cancer is unclear.

Preliminary data suggest that increased sensitivity to radiation could be a cause of cancer susceptibility in carriers of BRCA1 and BRCA2 mutations,[33,34,35,36] and in association with germline ATM and TP53 mutations.[37,38] Since BRCA1/2 mutation carriers are heterozygotes, however, radiation sensitivity might occur only after a somatic mutation has damaged the normal copy of the gene.

The possibility that genetic susceptibility to breast cancer occurs via a mechanism of radiation sensitivity raises questions about radiation exposure. It is possible that diagnostic radiation exposure, including mammography, poses more risk in genetically susceptible women than in women of average risk. Therapeutic radiation could also pose carcinogenic risk. A cohort study of BRCA1 and BRCA2 mutation carriers treated with breast-conserving therapy, however, showed no evidence of increased radiation sensitivity or sequelae in the breast, lung, or bone marrow of mutation carriers.[39] Conversely, radiation sensitivity could make tumors in women with genetic susceptibility to breast cancer more responsive to radiation treatment. Studies examining the impact of mammography and chest x-ray exposure in BRCA1 and BRCA2 mutation carriers have had conflicting results.[40,41] (Refer to text on Radiation in the Interventions section of this summary for more information.)

Alcohol intake

The risk of breast cancer increases by approximately 10% for each 10g of daily alcohol intake (approximately 1 drink or less) in the general population.[42,43] One study of BRCA1/BRCA2 mutation carriers found no increased risk associated with alcohol consumption.[44]

Physical activity and anthropometry

Weight gain and being overweight are commonly recognized risk factors for breast cancer. In general, overweight women are most commonly observed to be at increased risk of postmenopausal breast cancer and at reduced risk of premenopausal breast cancer. Sedentary lifestyle may also be a risk factor.[45] These factors have not been systematically evaluated in women with a positive family history of breast cancer or in carriers of cancer-predisposing mutations, but one study suggested a reduced risk of cancer associated with exercise among BRCA1 and BRCA2 mutation carriers.[46]

Benign breast disease and mammographic density

Benign breast disease (BBD) is a risk factor for breast cancer, independent of the effects of other major risk factors for breast cancer (age, age at menarche, age at first live birth, and family history of breast cancer).[47] There may also be an association between benign breast disease and family history of breast cancer.[48]

An increased risk of breast cancer has also been demonstrated for women who have increased density of breast tissue as assessed by mammogram,[47,49,50] and breast density may have a genetic component in its etiology.[51,52,53]

Other factors

Other risk factors, including those that are only weakly associated with breast cancer and those that have been inconsistently associated with the disease in epidemiologic studies (e.g., cigarette smoking), may be important in subgroups of women defined according to genotype. For example, some studies have suggested that certain N-acetyl transferase alleles may influence female smokers' risk of developing breast cancer.[54] One study [55] found a reduced risk of breast cancer among BRCA1/2 mutation carriers who smoked, but an expanded follow-up study failed to find an association.[56]

Other Risk Factors for Ovarian Cancer

Factors that increase risk for ovarian cancer include increasing age and nulliparity, while those that decrease risk include surgical history and oral contraceptives.[57,58] (Refer to the PDQ summary on Prevention of Ovarian Cancer for more information.) Relatively few studies have addressed the effect of these risk factors in women who are genetically susceptible to ovarian cancer. (Refer to the Risk Modification section for more information.)

Age

Ovarian cancer incidence rises in a linear fashion from age 30 years to age 50 years and continues to increase, though at a slower rate, thereafter. Before age 30 years, the risk of developing epithelial ovarian cancer is remote; even in hereditary cancer families.[59]

Reproductive history

Nulliparity is consistently associated with an increased risk of ovarian cancer, including among BRCA1/BRCA2 mutation carriers.[60] Risk may also be increased among women who have used fertility drugs, especially those who remain nulligravid.[57,61] Evidence is growing that the use of menopausal HRT is associated with an increased risk of ovarian cancer, particularly in long-time users and users of sequential estrogen-progesterone schedules.[62,63,64,65]

Surgical history

Bilateral tubal ligation and hysterectomy are associated with reduced ovarian cancer risk,[57,66,67] including in BRCA1/BRCA2 mutation carriers.[68] Ovarian cancer risk is reduced more than 90% in women with documented BRCA1 or BRCA2 mutations who chose risk-reducing salpingo-oophorectomy (RRSO). In this same population, prophylactic removal of the ovaries also resulted in a nearly 50% reduction in the risk of subsequent breast cancer.[69,70] For further information on these studies refer to the Risk-Reducing Salpingo-Oophorectomy section of this summary.

Oral contraceptives

Use of oral contraceptives for 4 or more years is associated with an approximately 50% reduction in ovarian cancer risk in the general population.[57,58] A majority of, but not all, studies also support oral contraceptives being protective among BRCA1/ BRCA2 mutation carriers.[60,71,72,73,74]

Models for Prediction of Breast Cancer Risk

Models to predict an individual's lifetime risk for developing breast cancer are available. In addition, models exist to predict an individual's likelihood of having a BRCA1 or BRCA2 mutation. (For further information on these models, refer to the Models for Prediction of the Likelihood of a BRCA1 or BRCA2 Mutation section of this summary.) Not all models can be appropriately applied for all patients. Each model is appropriate only when the patient's characteristics and family history are similar to the study population on which the model was based. The table, Characteristics of the Gail and Claus Models, summarizes the salient aspects of two of the common risk assessment models and is designed to aid in choosing the one that best applies to a particular individual.

The Claus model [75,76] and the Gail model[77] are widely used in research studies and clinical counseling. Both have limitations, and the risk estimates derived from the two models may differ for an individual patient. Several other models, which include more detailed family history information, are also in use and are discussed below.

Table 1. Characteristics of the Gail and Claus Modelsa

a Adapted from Domchek et al.,[78] Rubenstein et al.,[79] and Rhodes.[80]
  Gail Model Claus Model
DATA DERIVED FROM Breast Cancer Detection Demonstration Project Study Cancer and Steroid Hormone Study
STUDY POPULATION 2,852 cases, aged =35 years 4,730 cases, aged 20–54 years
In situ and invasive cancer Invasive cancer
3,146 controls 4,688 controls
Caucasian Caucasian
Annual breast screening Not routinely screened
FAMILY HISTORY CHARACTERISTICS First-degree relatives with breast cancer First-degree or second-degree relatives with breast cancer
Age of onset in relatives
OTHER CHARACTERISTICS Current age Current age
Age at menarche
Age at first live birth
Number of breast biopsies
Atypical hyperplasia in breast biopsy
Race (included in the most current version of the Gail model)
STRENGTHS Incorporates: Incorporates:
Risk factors other than family history Paternal as well as maternal history
Age at onset of breast cancer
Family history of ovarian cancer
LIMITATIONS Underestimates risk in hereditary families May underestimate risk in hereditary families
Number of breast biopsies without atypical hyperplasia may cause inflated risk estimates May not be applicable to all combinations of affected relatives
Does not include risk factors other than family history
Does not incorporate:  
Paternal family history of breast cancer or any family history of ovarian cancer
Age at onset of breast cancer in relatives
All known risk factors for breast cancer [80]
BEST APPLICATION For individuals with no family history of breast cancer or 1 first-degree relative with breast cancer, aged =50 years For individuals with 0, 1, or 2 first-degree or second-degree relatives with breast cancer
For determining eligibility for chemoprevention studies

It is important to note that the Gail and the Claus models will significantly underestimate breast cancer risk for women in families with hereditary breast cancer susceptibility syndromes. Generally, the Claus or the Gail models should not be the sole model used for families with one of the following characteristics:

  • Three individuals with breast or ovarian cancer (especially when one or more breast cancers are diagnosed before age 50 years).
  • A woman who has both breast and ovarian cancer.
  • Ashkenazi Jewish ancestry with at least one case of breast or ovarian cancer (as these families are more likely to have a hereditary cancer susceptibility syndrome).

The Gail model is the basis for the Breast Cancer Risk Assessment Tool, a computer program that is available from the NCI by calling the Cancer Information Service at 1-800-4-CANCER (1-800-422-6237, or TTY at 1-800-332-8615). This version of the Gail model estimates only the risk of invasive breast cancer. The Gail model has been found to be reasonably accurate at predicting breast cancer risk in large groups of white women who undergo annual screening mammography.[81,82,83,84,85] While the model is reliable in predicting the number of breast cancer cases expected in a group of women from the same age-risk strata, it is less reliable in predicting risk for individual patients. Risk can be overestimated in:

  • Nonadherent women (i.e., does not adhere to screening recommendations).[81,82]
  • Women in the highest risk strata.[84]

Risk could be underestimated in the lowest risk strata.[84] Earlier studies [81,82] suggested risk was overestimated in younger women and underestimated in older women. More recent studies [83,84] using the modified Gail model (which is currently used) found it performed well in all age groups. Further studies are needed to establish the validity of the Gail model in minority populations.[85] Recently, modifications have been made to the Breast Cancer Risk Assessment Tool incorporating data from the Women's Contraceptive and Reproductive Experiences (CARE) study. This study of over 1,600 African American women with invasive breast cancer and over 1,600 controls was used to develop a breast cancer risk assessment model with improved race-specific calibration.[86]

A study of 491 women aged 18 to 74 years with a family history of breast cancer compared the most recent Gail model to the Claus model in predicting breast cancer risk.[87] The two models were positively correlated (r = .55). The Gail model estimates were higher than the Claus model estimates for most participants. Presentation and discussion of both the Gail and Claus models risk estimates may be useful in the counseling setting.

The Tyrer-Cuzick model incorporates both genetic and non-genetic factors.[88] A three-generation pedigree is used to estimate the likelihood that an individual carries either a BRCA1/BRCA2 mutation or a hypothetical low penetrance gene. In addition, the model incorporates personal risk factors such as parity, body mass index, height, and age at menarche, menopause and first live birth. Both genetic and nongenetic factors are combined to develop a risk estimate. Although powerful, the model at the current time is less accessible to primary care providers than the Gail and Claus models. The BOADICEA model examines family history to estimate breast cancer risk and also incorporates both BRCA1/2 and non-BRCA1/2 genetic risk factors.[89]

Other models incorporating breast density have been developed but are not ready for clinical use.[90,91] In the future, models may be developed or refined to include such factors as breast density and other biomarkers.

References:

1. American Cancer Society.: Cancer Facts and Figures 2009. Atlanta, Ga: American Cancer Society, 2009. Also available online. Last accessed January 6, 2010.
2. Ravdin PM, Cronin KA, Howlader N, et al.: The decrease in breast-cancer incidence in 2003 in the United States. N Engl J Med 356 (16): 1670-4, 2007.
3. Yang Q, Khoury MJ, Rodriguez C, et al.: Family history score as a predictor of breast cancer mortality: prospective data from the Cancer Prevention Study II, United States, 1982-1991. Am J Epidemiol 147 (7): 652-9, 1998.
4. Colditz GA, Willett WC, Hunter DJ, et al.: Family history, age, and risk of breast cancer. Prospective data from the Nurses' Health Study. JAMA 270 (3): 338-43, 1993.
5. Slattery ML, Kerber RA: A comprehensive evaluation of family history and breast cancer risk. The Utah Population Database. JAMA 270 (13): 1563-8, 1993.
6. Johnson N, Lancaster T, Fuller A, et al.: The prevalence of a family history of cancer in general practice. Fam Pract 12 (3): 287-9, 1995.
7. Pharoah PD, Day NE, Duffy S, et al.: Family history and the risk of breast cancer: a systematic review and meta-analysis. Int J Cancer 71 (5): 800-9, 1997.
8. Stratton JF, Pharoah P, Smith SK, et al.: A systematic review and meta-analysis of family history and risk of ovarian cancer. Br J Obstet Gynaecol 105 (5): 493-9, 1998.
9. Lindor NM, McMaster ML, Lindor CJ, et al.: Concise handbook of familial cancer susceptibility syndromes - second edition. J Natl Cancer Inst Monogr (38): 1-93, 2008.
10. Kerber RA, Slattery ML: Comparison of self-reported and database-linked family history of cancer data in a case-control study. Am J Epidemiol 146 (3): 244-8, 1997.
11. Parent ME, Ghadirian P, Lacroix A, et al.: The reliability of recollections of family history: implications for the medical provider. J Cancer Educ 12 (2): 114-20, 1997 Summer.
12. Key TJ, Verkasalo PK, Banks E: Epidemiology of breast cancer. Lancet Oncol 2 (3): 133-40, 2001.
13. Hankinson S, Hunter D: Breast cancer. In: Adami H, Hunter D, Trichopoulos D, eds.: Textbook of Cancer Epidemiology. New York, NY: Oxford University Press, 2002, pp 301-39.
14. Narod SA: Modifiers of risk of hereditary breast and ovarian cancer. Nat Rev Cancer 2 (2): 113-23, 2002.
15. Feuer EJ, Wun LM, Boring CC, et al.: The lifetime risk of developing breast cancer. J Natl Cancer Inst 85 (11): 892-7, 1993.
16. Antoniou AC, Shenton A, Maher ER, et al.: Parity and breast cancer risk among BRCA1 and BRCA2 mutation carriers. Breast Cancer Res 8 (6): R72, 2006.
17. Breast cancer and hormonal contraceptives: collaborative reanalysis of individual data on 53 297 women with breast cancer and 100 239 women without breast cancer from 54 epidemiological studies. Collaborative Group on Hormonal Factors in Breast Cancer. Lancet 347 (9017): 1713-27, 1996.
18. Ursin G, Henderson BE, Haile RW, et al.: Does oral contraceptive use increase the risk of breast cancer in women with BRCA1/BRCA2 mutations more than in other women? Cancer Res 57 (17): 3678-81, 1997.
19. Narod SA, Dubé MP, Klijn J, et al.: Oral contraceptives and the risk of breast cancer in BRCA1 and BRCA2 mutation carriers. J Natl Cancer Inst 94 (23): 1773-9, 2002.
20. Milne RL, Knight JA, John EM, et al.: Oral contraceptive use and risk of early-onset breast cancer in carriers and noncarriers of BRCA1 and BRCA2 mutations. Cancer Epidemiol Biomarkers Prev 14 (2): 350-6, 2005.
21. Breast cancer and hormone replacement therapy: collaborative reanalysis of data from 51 epidemiological studies of 52,705 women with breast cancer and 108,411 women without breast cancer. Collaborative Group on Hormonal Factors in Breast Cancer. Lancet 350 (9084): 1047-59, 1997.
22. Writing Group for the Women's Health Initiative Investigators.: Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results From the Women's Health Initiative randomized controlled trial. JAMA 288 (3): 321-33, 2002.
23. Chlebowski RT, Hendrix SL, Langer RD, et al.: Influence of estrogen plus progestin on breast cancer and mammography in healthy postmenopausal women: the Women's Health Initiative Randomized Trial. JAMA 289 (24): 3243-53, 2003.
24. Beral V; Million Women Study Collaborators.: Breast cancer and hormone-replacement therapy in the Million Women Study. Lancet 362 (9382): 419-27, 2003.
25. Anderson GL, Limacher M, Assaf AR, et al.: Effects of conjugated equine estrogen in postmenopausal women with hysterectomy: the Women's Health Initiative randomized controlled trial. JAMA 291 (14): 1701-12, 2004.
26. Schuurman AG, van den Brandt PA, Goldbohm RA: Exogenous hormone use and the risk of postmenopausal breast cancer: results from The Netherlands Cohort Study. Cancer Causes Control 6 (5): 416-24, 1995.
27. Steinberg KK, Thacker SB, Smith SJ, et al.: A meta-analysis of the effect of estrogen replacement therapy on the risk of breast cancer. JAMA 265 (15): 1985-90, 1991.
28. Sellers TA, Mink PJ, Cerhan JR, et al.: The role of hormone replacement therapy in the risk for breast cancer and total mortality in women with a family history of breast cancer. Ann Intern Med 127 (11): 973-80, 1997.
29. Stanford JL, Weiss NS, Voigt LF, et al.: Combined estrogen and progestin hormone replacement therapy in relation to risk of breast cancer in middle-aged women. JAMA 274 (2): 137-42, 1995.
30. Colditz GA, Egan KM, Stampfer MJ: Hormone replacement therapy and risk of breast cancer: results from epidemiologic studies. Am J Obstet Gynecol 168 (5): 1473-80, 1993.
31. Gorsky RD, Koplan JP, Peterson HB, et al.: Relative risks and benefits of long-term estrogen replacement therapy: a decision analysis. Obstet Gynecol 83 (2): 161-6, 1994.
32. Rebbeck TR, Friebel T, Wagner T, et al.: Effect of short-term hormone replacement therapy on breast cancer risk reduction after bilateral prophylactic oophorectomy in BRCA1 and BRCA2 mutation carriers: the PROSE Study Group. J Clin Oncol 23 (31): 7804-10, 2005.
33. Helzlsouer KJ, Harris EL, Parshad R, et al.: Familial clustering of breast cancer: possible interaction between DNA repair proficiency and radiation exposure in the development of breast cancer. Int J Cancer 64 (1): 14-7, 1995.
34. Helzlsouer KJ, Harris EL, Parshad R, et al.: DNA repair proficiency: potential susceptiblity factor for breast cancer. J Natl Cancer Inst 88 (11): 754-5, 1996.
35. Abbott DW, Thompson ME, Robinson-Benion C, et al.: BRCA1 expression restores radiation resistance in BRCA1-defective cancer cells through enhancement of transcription-coupled DNA repair. J Biol Chem 274 (26): 18808-12, 1999.
36. Abbott DW, Freeman ML, Holt JT: Double-strand break repair deficiency and radiation sensitivity in BRCA2 mutant cancer cells. J Natl Cancer Inst 90 (13): 978-85, 1998.
37. Easton DF: Cancer risks in A-T heterozygotes. Int J Radiat Biol 66 (6 Suppl): S177-82, 1994.
38. Kleihues P, Schäuble B, zur Hausen A, et al.: Tumors associated with p53 germline mutations: a synopsis of 91 families. Am J Pathol 150 (1): 1-13, 1997.
39. Pierce LJ, Strawderman M, Narod SA, et al.: Effect of radiotherapy after breast-conserving treatment in women with breast cancer and germline BRCA1/2 mutations. J Clin Oncol 18 (19): 3360-9, 2000.
40. Narod SA, Lubinski J, Ghadirian P, et al.: Screening mammography and risk of breast cancer in BRCA1 and BRCA2 mutation carriers: a case-control study. Lancet Oncol 7 (5): 402-6, 2006.
41. Andrieu N, Easton DF, Chang-Claude J, et al.: Effect of chest X-rays on the risk of breast cancer among BRCA1/2 mutation carriers in the international BRCA1/2 carrier cohort study: a report from the EMBRACE, GENEPSO, GEO-HEBON, and IBCCS Collaborators' Group. J Clin Oncol 24 (21): 3361-6, 2006.
42. Smith-Warner SA, Spiegelman D, Yaun SS, et al.: Alcohol and breast cancer in women: a pooled analysis of cohort studies. JAMA 279 (7): 535-40, 1998.
43. Hamajima N, Hirose K, Tajima K, et al.: Alcohol, tobacco and breast cancer--collaborative reanalysis of individual data from 53 epidemiological studies, including 58,515 women with breast cancer and 95,067 women without the disease. Br J Cancer 87 (11): 1234-45, 2002.
44. McGuire V, John EM, Felberg A, et al.: No increased risk of breast cancer associated with alcohol consumption among carriers of BRCA1 and BRCA2 mutations ages <50 years. Cancer Epidemiol Biomarkers Prev 15 (8): 1565-7, 2006.
45. McTiernan A: Behavioral risk factors in breast cancer: can risk be modified? Oncologist 8 (4): 326-34, 2003.
46. King MC, Marks JH, Mandell JB, et al.: Breast and ovarian cancer risks due to inherited mutations in BRCA1 and BRCA2. Science 302 (5645): 643-6, 2003.
47. Chen J, Pee D, Ayyagari R, et al.: Projecting absolute invasive breast cancer risk in white women with a model that includes mammographic density. J Natl Cancer Inst 98 (17): 1215-26, 2006.
48. Dupont WD, Page DL, Parl FF, et al.: Long-term risk of breast cancer in women with fibroadenoma. N Engl J Med 331 (1): 10-5, 1994.
49. Boyd NF, Byng JW, Jong RA, et al.: Quantitative classification of mammographic densities and breast cancer risk: results from the Canadian National Breast Screening Study. J Natl Cancer Inst 87 (9): 670-5, 1995.
50. Byrne C, Schairer C, Wolfe J, et al.: Mammographic features and breast cancer risk: effects with time, age, and menopause status. J Natl Cancer Inst 87 (21): 1622-9, 1995.
51. Pankow JS, Vachon CM, Kuni CC, et al.: Genetic analysis of mammographic breast density in adult women: evidence of a gene effect. J Natl Cancer Inst 89 (8): 549-56, 1997.
52. Boyd NF, Lockwood GA, Martin LJ, et al.: Mammographic densities and risk of breast cancer among subjects with a family history of this disease. J Natl Cancer Inst 91 (16): 1404-8, 1999.
53. Vachon CM, King RA, Atwood LD, et al.: Preliminary sibpair linkage analysis of percent mammographic density. J Natl Cancer Inst 91 (20): 1778-9, 1999.
54. Ambrosone CB, Freudenheim JL, Graham S, et al.: Cigarette smoking, N-acetyltransferase 2 genetic polymorphisms, and breast cancer risk. JAMA 276 (18): 1494-501, 1996.
55. Brunet JS, Ghadirian P, Rebbeck TR, et al.: Effect of smoking on breast cancer in carriers of mutant BRCA1 or BRCA2 genes. J Natl Cancer Inst 90 (10): 761-6, 1998.
56. Ghadirian P, Lubinski J, Lynch H, et al.: Smoking and the risk of breast cancer among carriers of BRCA mutations. Int J Cancer 110 (3): 413-6, 2004.
57. Whittemore AS, Harris R, Itnyre J: Characteristics relating to ovarian cancer risk: collaborative analysis of 12 US case-control studies. II. Invasive epithelial ovarian cancers in white women. Collaborative Ovarian Cancer Group. Am J Epidemiol 136 (10): 1184-203, 1992.
58. John EM, Whittemore AS, Harris R, et al.: Characteristics relating to ovarian cancer risk: collaborative analysis of seven U.S. case-control studies. Epithelial ovarian cancer in black women. Collaborative Ovarian Cancer Group. J Natl Cancer Inst 85 (2): 142-7, 1993.
59. Amos CI, Struewing JP: Genetic epidemiology of epithelial ovarian cancer. Cancer 71 (2 Suppl): 566-72, 1993.
60. Modan B, Hartge P, Hirsh-Yechezkel G, et al.: Parity, oral contraceptives, and the risk of ovarian cancer among carriers and noncarriers of a BRCA1 or BRCA2 mutation. N Engl J Med 345 (4): 235-40, 2001.
61. Brinton LA, Lamb EJ, Moghissi KS, et al.: Ovarian cancer risk after the use of ovulation-stimulating drugs. Obstet Gynecol 103 (6): 1194-203, 2004.
62. Rodriguez C, Patel AV, Calle EE, et al.: Estrogen replacement therapy and ovarian cancer mortality in a large prospective study of US women. JAMA 285 (11): 1460-5, 2001.
63. Riman T, Dickman PW, Nilsson S, et al.: Hormone replacement therapy and the risk of invasive epithelial ovarian cancer in Swedish women. J Natl Cancer Inst 94 (7): 497-504, 2002.
64. Lacey JV Jr, Mink PJ, Lubin JH, et al.: Menopausal hormone replacement therapy and risk of ovarian cancer. JAMA 288 (3): 334-41, 2002.
65. Anderson GL, Judd HL, Kaunitz AM, et al.: Effects of estrogen plus progestin on gynecologic cancers and associated diagnostic procedures: the Women's Health Initiative randomized trial. JAMA 290 (13): 1739-48, 2003.
66. Tortolero-Luna G, Mitchell MF: The epidemiology of ovarian cancer. J Cell Biochem Suppl 23: 200-7, 1995.
67. Hankinson SE, Hunter DJ, Colditz GA, et al.: Tubal ligation, hysterectomy, and risk of ovarian cancer. A prospective study. JAMA 270 (23): 2813-8, 1993.
68. Rutter JL, Wacholder S, Chetrit A, et al.: Gynecologic surgeries and risk of ovarian cancer in women with BRCA1 and BRCA2 Ashkenazi founder mutations: an Israeli population-based case-control study. J Natl Cancer Inst 95 (14): 1072-8, 2003.
69. Kauff ND, Satagopan JM, Robson ME, et al.: Risk-reducing salpingo-oophorectomy in women with a BRCA1 or BRCA2 mutation. N Engl J Med 346 (21): 1609-15, 2002.
70. Rebbeck TR, Lynch HT, Neuhausen SL, et al.: Prophylactic oophorectomy in carriers of BRCA1 or BRCA2 mutations. N Engl J Med 346 (21): 1616-22, 2002.
71. Narod SA, Risch H, Moslehi R, et al.: Oral contraceptives and the risk of hereditary ovarian cancer. Hereditary Ovarian Cancer Clinical Study Group. N Engl J Med 339 (7): 424-8, 1998.
72. Narod SA, Sun P, Ghadirian P, et al.: Tubal ligation and risk of ovarian cancer in carriers of BRCA1 or BRCA2 mutations: a case-control study. Lancet 357 (9267): 1467-70, 2001.
73. Whittemore AS, Balise RR, Pharoah PD, et al.: Oral contraceptive use and ovarian cancer risk among carriers of BRCA1 or BRCA2 mutations. Br J Cancer 91 (11): 1911-5, 2004.
74. McGuire V, Felberg A, Mills M, et al.: Relation of contraceptive and reproductive history to ovarian cancer risk in carriers and noncarriers of BRCA1 gene mutations. Am J Epidemiol 160 (7): 613-8, 2004.
75. Claus EB, Risch N, Thompson WD: Autosomal dominant inheritance of early-onset breast cancer. Implications for risk prediction. Cancer 73 (3): 643-51, 1994.
76. Claus EB, Risch N, Thompson WD: The calculation of breast cancer risk for women with a first degree family history of ovarian cancer. Breast Cancer Res Treat 28 (2): 115-20, 1993.
77. Gail MH, Brinton LA, Byar DP, et al.: Projecting individualized probabilities of developing breast cancer for white females who are being examined annually. J Natl Cancer Inst 81 (24): 1879-86, 1989.
78. Domchek SM, Eisen A, Calzone K, et al.: Application of breast cancer risk prediction models in clinical practice. J Clin Oncol 21 (4): 593-601, 2003.
79. Rubinstein WS, O'Neill SM, Peters JA, et al.: Mathematical modeling for breast cancer risk assessment. State of the art and role in medicine. Oncology (Huntingt) 16 (8): 1082-94; discussion 1094, 1097-9, 2002.
80. Rhodes DJ: Identifying and counseling women at increased risk for breast cancer. Mayo Clin Proc 77 (4): 355-60; quiz 360-1, 2002.
81. Bondy ML, Lustbader ED, Halabi S, et al.: Validation of a breast cancer risk assessment model in women with a positive family history. J Natl Cancer Inst 86 (8): 620-5, 1994.
82. Spiegelman D, Colditz GA, Hunter D, et al.: Validation of the Gail et al. model for predicting individual breast cancer risk. J Natl Cancer Inst 86 (8): 600-7, 1994.
83. Rockhill B, Spiegelman D, Byrne C, et al.: Validation of the Gail et al. model of breast cancer risk prediction and implications for chemoprevention. J Natl Cancer Inst 93 (5): 358-66, 2001.
84. Costantino JP, Gail MH, Pee D, et al.: Validation studies for models projecting the risk of invasive and total breast cancer incidence. J Natl Cancer Inst 91 (18): 1541-8, 1999.
85. Bondy ML, Newman LA: Breast cancer risk assessment models: applicability to African-American women. Cancer 97 (1 Suppl): 230-5, 2003.
86. Gail MH, Costantino JP, Pee D, et al.: Projecting individualized absolute invasive breast cancer risk in African American women. J Natl Cancer Inst 99 (23): 1782-92, 2007.
87. McTiernan A, Kuniyuki A, Yasui Y, et al.: Comparisons of two breast cancer risk estimates in women with a family history of breast cancer. Cancer Epidemiol Biomarkers Prev 10 (4): 333-8, 2001.
88. Tyrer J, Duffy SW, Cuzick J: A breast cancer prediction model incorporating familial and personal risk factors. Stat Med 23 (7): 1111-30, 2004.
89. Antoniou AC, Pharoah PP, Smith P, et al.: The BOADICEA model of genetic susceptibility to breast and ovarian cancer. Br J Cancer 91 (8): 1580-90, 2004.
90. Barlow WE, White E, Ballard-Barbash R, et al.: Prospective breast cancer risk prediction model for women undergoing screening mammography. J Natl Cancer Inst 98 (17): 1204-14, 2006.
91. Tice JA, Cummings SR, Ziv E, et al.: Mammographic breast density and the Gail model for breast cancer risk prediction in a screening population. Breast Cancer Res Treat 94 (2): 115-22, 2005.

Major Genes

Introduction

Epidemiologic studies have clearly established the role of family history as an important risk factor for both breast and ovarian cancer. After gender and age, a positive family history is the strongest known predictive risk factor for breast cancer. In most cases an extensive family history (more than four relatives in the same biologic line affected) is not present. However, it has long been recognized that in some families, there is hereditary breast cancer, which is characterized by an early age of onset, bilaterality, and the presence of breast cancer in multiple generations through either the maternal or paternal lines in an apparent autosomal dominant pattern of transmission and familial association with tumors of other organs, particularly the ovary and prostate gland.[1,2] We now know that some of these "cancer families" can be explained by specific mutations in single cancer susceptibility genes. The isolation of several of these genes, which when mutated are associated with a significantly increased risk of breast/ovarian cancer, makes it possible to identify individuals at risk. Although such cancer susceptibility genes are very important, only 5% to10% of individuals who develop breast cancer are known to carry highly penetrant gene mutations.

A 1988 study reported the first quantitative evidence that breast cancer segregated as an autosomal dominant trait in some families.[3] The search for genes associated with hereditary susceptibility to breast cancer has been facilitated by the study of large kindreds with multiple affected individuals, and has led to the identification of several susceptibility genes, including BRCA1, BRCA2, TP53, PTEN/MMAC1, and STK11. Other genes, such as the mismatch repair genes MLH1 and MSH2, have been associated with an increased risk of ovarian cancer, but have not been consistently associated with breast cancer.

BRCA1

In 1990, a susceptibility gene for breast cancer was mapped by genetic linkage to the long arm of chromosome 17, in the interval 17q12-21.[4] The linkage between breast cancer and genetic markers on chromosome 17q was soon confirmed by others, and evidence for the coincident transmission of both breast and ovarian cancer susceptibility in linked families was observed.[5] The BRCA1 gene (OMIM) was subsequently identified by positional cloning methods and has been found to contain 24 exons that encode a protein of 1,863 amino acids. Mutations in BRCA1 are associated with early-onset breast cancer, ovarian cancer, and fallopian tube cancer. (Refer to the Penetrance section for more information.) Male breast cancer, pancreatic cancer, testicular cancer, and early-onset prostate cancer may also be associated with mutations in BRCA1;[6,7,8,9] however, male breast cancer, pancreatic cancer, and prostate cancer are more strongly associated with mutations in BRCA2.

BRCA2

A second breast cancer susceptibility gene, BRCA2, was localized to the long arm of chromosome 13 through linkage studies of 15 families with multiple cases of breast cancer that were not linked to BRCA1. Mutations in BRCA2 (OMIM) are associated with multiple cases of breast cancer in families, and are also associated with male breast cancer, ovarian cancer, prostate cancer, melanoma, and pancreatic cancer.[8,9,10,11,12,13] (Refer to the Penetrance section for more information.) BRCA2 is also a large gene with 27 exons that encode a protein of 3,418 amino acids.[14] While not homologous genes, both BRCA1 and BRCA2 have an unusually large exon 11 and translational start sites in exon 2. Like BRCA1, BRCA2 appears to behave like a tumor suppressor gene. In tumors associated with both BRCA1 and BRCA2 mutations, there is often loss of the wild-type (unmutated) allele.

Mutations in BRCA1 and BRCA2 appear to be responsible for disease in 45% of families with multiple cases of breast cancer only and in up to 90% of families with both breast and ovarian cancer.[15]

BRCA1 and BRCA2 Function

Most BRCA1 and BRCA2 mutations are predicted to produce a truncated protein product, and thus loss of protein function, although some missense mutations cause loss of function without truncation. Because inherited breast/ovarian cancer is an autosomal dominant condition, persons with a BRCA1 or BRCA2 mutation on one copy of chromosome 17 or 13 also carry a normal allele on the other paired chromosome. In most breast and ovarian cancers that have been studied from mutation carriers, however, the normal allele is deleted, resulting in loss of all function. This finding strongly suggests that BRCA1 and BRCA2 are in the class of tumor suppressor genes, i.e., genes whose loss of function can result in neoplastic growth.[16,17]

In addition to, and as part of, their roles as tumor suppressor genes, BRCA1 and BRCA2 are involved in a myriad of functions within cells including homologous DNA repair, genomic stability, transcriptional regulation, and cell cycle control.[18,19]

Mutations in BRCA1 and BRCA2

Nearly 2,000 distinct mutations and sequence variations in BRCA1 and BRCA2 have already been described.[20] Approximately one in 400 to 800 individuals in the general population may carry a pathogenic mutation in BRCA1 and BRCA2.[21,22] The mutations that have been associated with increased risk of cancer result in missing or nonfunctional proteins, supporting the hypothesis that BRCA1 and BRCA2 are tumor suppressor genes. While a small number of these mutations have been found repeatedly in unrelated families, most have not been reported in more than a few families.

Mutation-screening methods vary in their sensitivity. Methods widely used in research laboratories, such as single-stranded conformational polymorphism (SSCP) analysis and conformation-sensitive gel electrophoresis (CSGE), miss nearly a third of the mutations that are detected by DNA sequencing.[23] In addition, large genomic rearrangements are missed by most of the techniques, including direct DNA sequencing, but testing for these is commercially available. Such rearrangements are believed to be responsible for 12% to 18% of BRCA1 inactivating mutations but are less common in BRCA2 and in individuals of Ashkenazi Jewish descent.[24,25,26]

Variants of uncertain significance

Germlinedeleterious mutations in the BRCA1/BRCA2 genes are associated with an approximately 60% lifetime risk of breast cancer and a 15% to 40% lifetime risk of ovarian cancer. There are no definitive functional tests for BRCA1 or BRCA2; therefore, classifying deleterious nucleotide changes to predict their functional impact relies on imperfect data. The majority of accepted deleterious mutations result in protein truncation and/or loss of important functional domains. However, 10% to 15% of all individuals undergoing genetic testing with full sequencing of BRCA1 and BRCA2 will not have a clearly deleterious mutation detected but will have a variant of uncertain (or unknown) significance (VUS). Variants of uncertain significance may cause substantial problems in counseling, particularly in terms of cancer risk estimates and risk management. Clinical management of such patients needs to be highly individualized and must take into consideration factors such as the patient's personal and family cancer history, as well as the likelihood that the VUS is deleterious, thus an improved classification and reporting system may be of clinical utility.[27]

African Americans appear to have a higher rate of VUS.[28] A comprehensive analysis examined the results of 7,461 consecutive full gene sequence analyses performed by Myriad Genetic Laboratories, Inc., over a 3-year period.[29] Among subjects who had no clearly deleterious mutation, 13% had VUS defined as "missense mutations and mutations that occur in analyzed intronic regions whose clinical significance has not yet been determined, chain-terminating mutations that truncate BRCA1 and BRCA2 distal to amino acid positions 1853 and 3308, respectively, and mutations that eliminate the normal stop codons for these proteins." The classification of a sequence variant as a VUS is a moving target. An additional 6.8% of individuals had sequence alterations that were once considered VUS, but were reclassified, usually as a polymorphism though occasionally as a deleterious mutation. In a 2009 study of data from Myriad, 16.5% of individuals of African ancestry had VUS, the highest rate among all ethnicities. Over time, the rate of changes classified as VUS has decreased in all ethnicities, largely due to improved mutation classification algorithms.[30] As additional information is accumulated, VUS are reclassified and such information may impact the continuing care of affected individuals.

A number of methods for discriminating deleterious from neutral VUS exist and others are in development [31,32,33,34] including integrated methods (see below).[35] Interpretation of VUS is greatly aided by efforts to track VUS in the family to determine if there is cosegregation of the VUS with the cancer in the family. Variant tracking is accomplished by testing parents and all affected family members (these costs are generally covered by Myriad Genetic Laboratory). The Myriad Genetic Laboratory typically provides additional information when a VUS is reported, including available data on cosegregation and whether the VUS has been seen in conjunction with a known deleterious mutation. In general, a VUS observed in subjects who also have a deleterious mutation, especially when it occurs with different mutations, is not felt to be in itself deleterious, although there are rare exceptions. As an adjunct to the clinical information, models to interpret VUS have been based on sequence conservation, biochemical properties of amino acid changes,[31,36,37,38,39,40] incorporation of information on pathologic characteristics of BRCA1- and BRCA2-related tumors (e.g., BRCA1-related breast cancers are usually estrogen receptor (ER)negative),[41] and functional studies to measure the influence of specific sequence variations on the activity of BRCA1 or BRCA2 proteins.[42,43] When attempting to interpret a VUS, all available information should be examined.

Prevalence and Founder Effects

Two large U.S. population-based studies of breast cancer patients younger than age 65 years examined the prevalence of BRCA1[44,45] and BRCA2[45] mutations in various ethnic groups. The prevalence of mutations by ethnic group was as follows:

BRCA1

  • 3.5% Hispanic.
  • 1.3% to 1.4% African American.
  • 0.5% Asian American.
  • 2.2% to 2.9% non-Ashkenazi Caucasian.
  • 8.3 % to 10.2% Ashkenazi Jewish.[44,45]

BRCA2

  • 2.6% African American.
  • 2.1% Caucasian.[45]

Among cases identified from the Cancer Surveillance System of Western Washington, the frequency of BRCA1 mutations was highest in cases diagnosed before age 30 years (23% carriers, 95% confidence interval [CI], 5.0–53.8), and in those with more than three relatives with breast cancer (20%, 95% CI, 6%–44%). A family history of ovarian cancer in a first-degree relative (FDR) was also associated with an increased prevalence of BRCA1 mutations (25%, 95% CI, 3.2%–65.1%).[46] In a second study, 263 women with familial breast cancer were analyzed.[47]BRCA1 mutations were found in 7% (95% CI, 0.3%–39%) of families with site-specific breast cancer, 18% of families with bilateral breast cancer, and 40% (95% CI, 1.7%–80.0%) of families with both breast and ovarian cancer. In a population-based series of incident cases of ovarian cancer in Canada, the overall prevalence of BRCA1/2 mutations was 11.7%; among women with a first-degree relative with breast or ovarian cancer, it was 19%. Of note, 6.5% of women with no affected first-degree relative carried a mutation, suggesting a higher overall prevalence of mutations in women with a diagnosis of ovarian cancer than in those with breast cancer.[45,48,49]

In some cases, the same mutation has been found in multiple apparently unrelated families. This observation is consistent with a founder effect. This occurs when a contemporary population can be traced back to a small, isolated group of founders. Most notably, two specific BRCA1 mutations (185delAG and 5382insC) and a BRCA2 mutation (6174delT) have been reported to be common in Ashkenazi Jews (those tracing their roots to Central and Eastern Europe). Carrier frequencies for these mutations have been determined in the general Jewish population: 0.9% (95% CI, 0.7%–1.1%) for the 185delAG mutation, 0.3% (95% CI, 0.2%–0.4%) for the 5382insC mutation, and 1.3% (95% CI, 1.0%–1.5%) for the BRCA2 6174delT mutation.[50,51,52,53] Altogether, the frequency of these three mutations approximates 1 in 40 among Ashkenazi Jews; they account for 25% of early-onset breast cancer, and up to 90% of families with multiple cases of both breast and ovarian cancer in this population.[54,55] Additional founder mutations have been described in multiple non-Ashkenazi Jewish populations including the Netherlands (BRCA1 2804delAA and several large deletion mutations), Iceland (BRCA2, 999del5), Portugal (BRCA2, exon 3 Alu insertion),[56] and Sweden (BRCA1, 3171ins5).[57,58,59,60]

The presence of these founder mutations has practical implications for genetic testing. Many laboratories offer directed testing specifically for ethnic-specific alleles. This greatly simplifies the technical aspects of the test but is not without pitfalls. It is estimated that up to 15% of BRCA1 and BRCA2 mutations that occur among Ashkenazim are nonfounder mutations.[29]

Models for Prediction of the Likelihood of a BRCA1 or BRCA2 Mutation

Several studies have assessed the frequency of BRCA1 or BRCA2 mutations in women with breast or ovarian cancer.[44,45,47,61,62,63,64,65,66,67] Personal characteristics associated with an increased likelihood of a BRCA1 or BRCA2 mutation include the following:

  • Breast cancer diagnosed at an early age.
  • Bilateral breast cancer.
  • A history of both breast and ovarian cancer.
  • The presence of breast cancer in one or more male family members.[47,61,62,63,66]

Family history characteristics associated with an increased likelihood of carrying a BRCA1 or BRCA2 mutation include the following:

  • Multiple cases of breast cancer in the family.
  • Both breast and ovarian cancer in the family.
  • One or more family members with two primary cancers.
  • Ashkenazi Jewish background.[47,61,62,63]

Many models have been developed to predict the probability of identifying germline BRCA1/2 mutations in individuals or families. These models include those using logistic regression,[29,47,61,63,66,68,69], "genetic" models using Bayesian analysis (BRCAPRO and BOADICEA),[66,70] and empiric observations,[45,48,50,51,71,72] including the Myriad prevalence tables. Two of the earliest models predicted only for BRCA1 mutations and are not clinically useful at this time.[47,61] More recently, using complex segregation analysis, a polygenetic model (BOADICEA) examining both breast cancer risk and the probability of having a BRCA1 or BRCA2 mutation has been published.[70] Prediction models have been shown to increase the discrimination power of even experienced providers in identifying patients in whom BRCA1/2 mutations are likely to be found.[73,74] Many of the models have been compared with each other in different studies and currently there is no one model that is consistently superior to others.[75,76,77,78] Most models do not include other cancers seen in the BRCA1 and BRCA2 spectrum such as pancreatic cancer and prostate cancer. Interventions that decrease the likelihood that an individual will develop cancer (such as oophorectomy and mastectomy) may influence the ability to predict BRCA1 and BRCA2 mutation status.[79] One study has shown that the risk models are sensitive to the amount of family history data available and perform less well with limited family information.[80]

The performance of the models can vary in specific ethnic groups. The BRCAPRO model appeared to best fit a series French Canadian families.[81] There have been variable results in the performance of the BRCAPRO model among Hispanics,[82,83] and both the BRCAPRO model and Myriad tables underestimated the proportion of mutation carriers in an Asian American population.[84] Further information is needed to determine which model performs best in each ethnic group.

Table 2. Characteristics of Common Models for Estimating the Likelihood of a BRCA 1/2 Mutation

AJ = Ashkenazi Jewish; BOADICEA = Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm; BRCAPRO = Berry-Aguilar-Parmigiani Model; FDR = first-degree relatives; SDR = second-degree relatives
  Myriad Prevalence Tables[63] BRCAPRO [66,79] BOADICEA [66,70] Tyrer-Cuzick [85]
METHOD Empiric data from Myriad Genetics based on family and personal history reported on requisition forms Statistical model Statistical model Statistical model
FEATURES OF THE MODEL Proband may or may not have breast or ovarian cancer Proband may or may not have breast or ovarian cancer Proband may or may not have breast or ovarian cancer Proband must be unaffected
Considers age of breast cancer diagnosis as <50, >50 Considers exact age at breast and ovarian cancer diagnosis
Does not consider affected relatives Considers prior genetic testing in family (i.e., BRCA1/2 mutation negative relatives) Considers exact age at breast and ovarian cancer diagnosis
Does not consider number of affected relatives Considers oophorectomy status Includes all FDR and SDR with and without cancer Also includes reproductive factors and body mass index to estimate breast cancer risk
Includes AJ ancestry Includes all FDR and SDR with and without cancer Includes AJ ancestry
Very easy to use Includes AJ ancestry
LIMITATIONS Simplified view of family structure Requires computer software and time-consuming data entry Requires computer software and time-consuming data entry Designed for individuals unaffected with breast cancer
Incorporates only FDR and SDR; may need to change proband to best capture risk Incorporates only FDR and SDR; may need to change proband to best capture risk
May overestimate risk in bilateral breast cancer [86]
May perform better in Caucasians than minority populations [83,87]

Genetic testing for BRCA1 and BRCA2 mutations has been available to the public since 1996. As more individuals have undergone testing, risk assessment models have improved. This, in turn, gives providers better data to estimate an individual patient's risk of carrying a mutation. There remains an art to risk assessment in practitioners' selection of the best model to fit their individual patient's circumstances and consideration of factors that might limit the ability to provide an accurate risk assessment (i.e., small family size, paucity of women, or ethnicity).

Penetrance of Mutations

The proportion of individuals carrying a mutation who will manifest the disease is referred to as penetrance. For adult-onset diseases, penetrance is usually dependent upon the individual carrier's age and sex. For example, the penetrance for breast cancer in female BRCA1/2 mutation carriers is often quoted by age 50 years (generally premenopausal) and by age 70 years. Of the numerous methods for estimating penetrance, none are without potential biases, and determining an individual mutation carrier's risk of cancer involves some level of imprecision.

Estimates of penetrance by age 70 years for BRCA1 and BRCA2 mutations show a large range, from 14% to 87% for breast cancer and 10% to 68% for ovarian cancer.[12,15,48,49,52,71,72,88,89,90,91,92,93,94,95,96,97,98,99,100,101] Initial penetrance estimates for BRCA1 and BRCA2 mutations were derived from multiple-case families from the Breast Cancer Linkage Consortium (BCLC), families studied to localize and clone the genes.[15,88,89] For breast cancer, the estimates ranged from 50% to 73% by age 50 years and 65% to 87% by age 70 years for BRCA1, and 59% and 82% at ages 50 years and 70 years, respectively, for BRCA2. For ovarian cancer, the estimates were as high as 29% by age 50 years and 63% by age 70 years.[88,89] For many patients currently seeking genetic testing for BRCA1 and BRCA2, the family history will not be as strong as this study by the BCLC (e.g., more than four affected relatives in the same biologic lineage) and therefore, these estimates may not apply.

In addition to the estimates from multiple-case families and patients from high-risk genetics clinics,[12,15,88,89,91,94,100,102] at least 13 studies have estimated penetrance by studying the families of mutation carriers who were not specifically recruited and studied because of a positive family history.[48,49,52,71,72,92,93,94,95,96,97,98,99] Often these studies have concentrated on founder populations in which testing of larger, more population-based subjects are possible owing to a reduced number of mutations that require testing,[52,71,90,92,95,96,98] compared with complete sequencing of the two genes required in most populations. The first study of a community-based series was carried out in the Washington, D.C., area. Blood samples and family medical histories were collected from more than 5,000 Ashkenazi Jewish individuals.[52] Study participants were tested for three founder mutations: 185delAG and 5382insC in BRCA1, and 6174delT in BRCA2. The prevalence of breast cancer in the relatives of carriers was compared with that reported by mutation-negative individuals. The risk of breast cancer in carriers of these mutations was estimated to be 56% (95% CI, 40%–73%) by age 70 years. Ovarian cancer risk was estimated to be 16% (95% CI, 6%–28%). These values were lower than most prior risk estimates. Men carrying BRCA1 and BRCA2 mutations were at modestly increased risk of prostate cancer, reaching 16% by age 70 years. Subsequent studies have provided additional support for an approximately twofold increased risk of prostate cancer in BRCA2 mutation carriers.[71,103,104].

Table 3. Penetrance of Cancer in BRCA1 and BRCA2 Mutation Carriers

+++ Multiple studies demonstrated association and are relatively consistent.
++ Multiple studies and the predominance of the evidence is positive.
+ May be an association, predominantly single studies; smaller limited studies and/or inconsistent but weighted toward positive.
+/- Mixed (some studies demonstrate an association and others do not).
- No association shown in studies of adequate size.
A = High (> 20%); B = Moderate (10–20%); C = Low (<10%); U = Undefined.
Cancer Sites [6,7,8,12,52,105] BRCA1 Mutation Carrier BRCA2 Mutation Carrier
  STRENGTH OF EVIDENCE MAGNITUDE OF ABSOLUTE RISK STRENGTH OF EVIDENCE MAGNITUDE OF ABSOLUTE RISK
KNOWN TO BE ASSOCIATED (WELL STUDIED)    
Breast (female) +++ A +++ A
Ovary, fallopian tube, peritoneum +++ A +++ B
Breast (male) + U +++ C
Pancreas ++ C +++ C
Prostate + U +++ A
THOUGHT NOT TO BE ASSOCIATED    
Colon/rectum -   -  
NOT ADEQUATELY STUDIED    
Melanoma (skin)     + C
Uterus +/- C    
Melanoma (uveal)     +/- C
Stomach     +/- C
Testicular +/- C    
Gallbladder/bile duct     +/- C
Bladder        
Head and neck        

The first Breast Cancer Linkage Consortium study investigating cancer risks reported an excess of colorectal cancer in BRCA1 carriers (RR = 4.1; 95% CI, 2.4–7.2).[88] This finding was supported by some family-based studies [6,7,106] but not all.[8,52,71,95,107,108,109] Furthermore, unselected series of colorectal cancer that have been exclusively performed in the Ashkenazi Jewish population have not shown elevated rates of BRCA1 or BRCA2 mutations.[110,111,112] Taken together, the data suggest little, if any, increased risk of colorectal cancer, and possibly only in specific population groups. Therefore, at this time, BRCA1 mutation carriers should adhere to population-screening recommendations.

Many subsequent studies, whether in founder or predominantly out bred populations, have estimated breast cancer risks by age 70 years of approximately 60% or lower and ovarian cancer risks of approximately 40% or lower, though often with large confidence limits because, even in studies of founder populations, the number of identified mutation carriers is relatively small. A meta-analysis of ten studies estimates risks among BRCA1 and BRCA2 mutation carriers of 57% and 49% for breast cancer and 40% and 18% for ovarian cancer.[113] Most studies have done molecular testing on the proband only and have done no,[48,52,71,72,90,92,94,95,96,98,99] or limited,[93,100] testing among relatives. Instead, the mutation status of relatives is modeled on simple Mendelian principles that on average, one-half of first-degree relatives of mutation carriers will themselves be carriers. Such modeling may lead to imprecision in the penetrance estimates; by chance, more than or less than half the relatives of some families will be carriers. In the New York Breast Cancer Study of 104 mutation-positive Ashkenazi Jews with breast cancer, penetrance estimates were based only on relatives whose mutation status was known.[49] These estimates were 69% and 74% for breast cancer by age 70 years for BRCA1 and BRCA2 mutation carriers, respectively, and 46% and 12% for ovarian cancer for BRCA1 and BRCA2, respectively.

The largest study to date to estimate penetrance involved a pooled analysis of 22 studies of over 8,000 breast and ovarian cancer cases unselected for family history.[99] Subjects were from 12 different countries and had a broad spectrum of mutations. Using modified segregation analysis on the families of the nearly 500 cases found to carry a BRCA1/2 mutation, the cumulative risk of breast cancer by age 70 years was 65% (95% CI, 44%–78%) for BRCA1 and 45% (95% CI, 31%–56%) for BRCA2. The penetrances for cancer are somewhat higher for BRCA1 mutation carriers, especially for ovarian cancer and early-onset breast cancer. These estimates are average risks of cancer among mutation carriers, assuming there is at least one family member with breast cancer or ovarian cancer (since all probands had these cancers), the situation likely to be encountered in clinical genetics situations. A case series of 491 women with stage I or stage II breast cancer and a known or suspected deleterious BRCA1/2 mutation was reviewed for incidence of ovarian cancer. The actuarial risk of developing ovarian cancer at 10 years following diagnosis of breast cancer was 12.7% for BRCA1 mutation carriers and 6.8% for BRCA2 mutation carriers. Eight of 83 cancer deaths (9.6%) in this series were because of ovarian cancer. Systemic treatment for the primary breast cancer did not alter these findings.[114] Several studies have suggested that cancer risks in BRCA1/BRCA2 mutation carriers are affected by the type of cancer of the index case. Relatives of breast cancer index cases were more likely to develop breast cancer, and relatives of ovarian cancer index cases were more likely to develop ovarian cancer.[99,115,116,117] Risk of breast cancer appears increased in more recent birth cohorts.[49,115]

The continuing uncertainty as to the exact penetrance for breast and ovarian cancer among BRCA1/2 mutation carriers may be due to several factors, including differences owing to study design, allelic heterogeneity (differing risks for different mutations within either of the genes), and to modifying genetic and/or environmental factors, such as differing rates of oophorectomy.[49,99,118,119,120,121,122] A large population-based family study found that the risk of breast cancer for relatives of probands with deleterious BRCA1/2 mutations demonstrated significant interfamilial variation, even when controlling for age at diagnosis of the proband and the presence of contralateral breast cancer.[123] While the average breast and ovarian cancer penetrances may not be as high as initially estimated, they are substantial, both in relative and absolute terms, and additional studies will be required to further characterize potential modifying factors in order to arrive at more precise individual risk projections. Precise penetrance estimates for less common cancers, such as pancreatic cancer, are lacking.

The tables titled "Studies of Cancer Penetrance Among BRCA1 and BRCA2 Mutation Carriers: Cumulative Incidence of Breast Cancer" and "Studies of Cancer Penetrance Among BRCA1 and BRCA2 Mutation Carriers: Cumulative Incidence of Ovarian Cancer" review the incidence of breast and ovarian cancer among BRCA1 and BRCA2 mutation carriers.

Table 4. Studies of Cancer Penetrance Among BRCA1 and BRCA2 Mutation Carriers: Cumulative Incidence of Breast Cancer

BCLC = Breast Cancer Linkage Consortium
a Outcome is breast OR ovarian cancer.
b Incidence to age 55 years.
c Incidence to age 75 years.
d Incidence to age 80 years.
  Cumulative Incidence of Breast Cancer to Given Age
  BRCA1 BRCA2 BRCA1/2
POPULATION 50 Y 70 Y 50 Y 70 Y 50 Y 70 Y
LINKAGE ANALYSIS-MAXIMIZATION OF LOGARITHM OF THE ODD (LOD) SCORE
—214 breast-ovary families (BCLC) [15]         59% 82%
—BRCA1-linked families (BCLC) [89] 51% 85%        
—237 breast and breast-ovarian cancer families (BCLC) [91] 49% 71% 28% 84%    
INCIDENCE OF SECOND CANCERS AFTER BREAST CANCER
—33 BRCA1-linked families (BCLC) [88] 73% 87%        
—BRCA1-linked families (BCLC) [89] 50% 65%        
ANALYSIS OF FAMILY MEMBERS
—Jewish ovarian cancer cases, 7 BRCA1, 3 BRCA2[90] 30%a 50%a 16%a 23%a    
—Jewish breast-ovary families, 16 BRCA1, 9 BRCA2[90] 37%a 64%a 18%a 49%a    
KIN COHORT USING FAMILY AND CANCER REGISTRIES
—Unselected Icelandic breast cancer patients, 56 female and 13 male BRCA2 995del5 [92]     17% 37%    
SECOND OR CONTRALATERAL CANCER INCIDENCE; FOCUS WAS ON NONBREAST AND OVARY OUTCOMES
—173 breast-ovarian cancer families either BRCA2-positive or BRCA2-linked (BCLC) [12]     37% 52%    
MODIFIED SEGREGATION ANALYSIS - ALL AVAILABLE RELATIVES TESTED (MENDEL)
—Australian population-based breast cancer, aged <40 years, 9 BRCA1, 9 BRCA2 [93]         10% 40%
KIN COHORT
—Community-based Washington, D.C. area Jews, 61 BRCA1, 59 BRCA2[52] 38% 59% 26% 51% 33% 56%
—Jewish women with breast cancer, 34 BRCA1, 15 BRCA2[71]   60%   28%    
—Jewish women with ovarian cancer, 44 BRCA1, 24 BRCA2[95] 31%b 44%c 6%b 37%c    
—Unselected cases ovarian cancer, 39 BRCA1, 21 BRCA2[48]   68%d   14%d    
MODIFIED SEGREGATION ANALYSIS (MENDEL)
—Breast cancer cases, aged <55 years, 8 BRCA1, 16 BRCA2[72] 32% 47% 18% 56% 21% 54%
—Families with 2+ cases ovarian cancer, 40 BRCA1, 11 BRCA2[94] 39% 72% 19% 71%    
—Unselected cases ovarian cancer, 12 BRCA1[94] 34% 50%        
—164 BRCA2-positive families from BCLC [97]       41%    
—Unselected cases ovarian or breast cancer from 22 studies, 289 BRCA1, 221 BRCA2[99] 38% 65% 15% 45%    
—Australian multiple-case families, 28 BRCA1, 23 BRCA2[100]   48%   74%    
RELATIVE RISK TIMES POPULATION RATES
—Jewish hospital-based ovarian cancer patients, 103 BRCA1, 44 BRCA2 founder mutations [96] 18% 59% 6% 38%    
DIRECT KAPLAN-MEIER ESTIMATES RESTRICTED TO RELATIVES KNOWN TO BE MUTATION POSITIVE
—Unselected Jewish breast cancer patients from NY, 67 BRCA1, 37 BRCA2[49] 39% 69% 34% 74%    
MENDELIAN RETROSPECTIVE LIKELIHOOD APPROACH
—U.S.-based through the Cancer Genetics Network, most counseling clinic-based, although smaller number population-based, 238 BRCA1, 143 BRCA2 [101]   46%   43%    

Table 5. Studies of Cancer Penetrance Among BRCA1 and BRCA2 Mutation Carriers: Cumulative Incidence of Ovarian Cancer

BCLC = Breast Cancer Linkage Consortium; LOD = logarithm of the odd
a Incidence to age 80 years
b Incidence to age 75 years
  Cumulative Incidence of Ovarian Cancer to Given Age
  BRCA1 BRCA2 BRCA1/2
POPULATION 50 Y 70 Y 50 Y 70 Y 50 Y 70 Y
INCIDENCE OF SECOND CANCERS AFTER BREAST CANCER
—33 BRCA1-linked families (BCLC) [88] 29% 44%        
—BRCA1-linked families (BCLC) [89] 29% 44%        
LINKAGE ANALYSIS - MAXIMIZATION OF LOD SCORE
—BRCA1-linked families (BCLC) [89] 23% 63%        
—237 breast and breast-ovarian cancer families (BCLC) [91]     0% 27%    
KIN COHORT
—Community-based Washington, D.C. area Jews, 61 BRCA1, 59 BRCA2[52] 8% 16% 5% 18% 7% 16%
—Unselected cases ovarian cancer, 39 BRCA1, 21 BRCA2[48]   36%a   10%a    
SECOND OR CONTRALATERAL CANCER INCIDENCE; FOCUS WAS ON NONBREAST AND OVARY OUTCOMES
—173 breast-ovarian cancer families either BRCA2-positive or BRCA2-linked (BCLC) [12]     3% 16%    
MODIFIED SEGREGATION ANALYSIS (MENDEL)
—Breast cancer cases, aged <55 years, 8 BRCA1, 16 BRCA2[72] 11% 36% 3% 10% 4% 16%
—Families with 2+ cases ovarian cancer, 40 BRCA1, 11 BRCA2[94] 17% 53% 1% 31%    
—Unselected cases ovarian cancer, 12 BRCA1[94] 21% 68%        
—164 BRCA2-positive families from BCLC [97]       14%    
—Unselected cases ovarian or breast cancer from 22 studies, 289 BRCA1, 221 BRCA2[99] 13% 39% 1% 11%    
RELATIVE RISK TIMES POPULATION RATES
—Jewish women with ovarian cancer, 44 BRCA1, 24 BRCA2[95]   >40%b   20%b    
—Unselected cases ovarian or breast cancer from 22 studies, 289 BRCA1, 221 BRCA2 [98] 11% 37% 3% 21%    
DIRECT KAPLAN-MEIER ESTIMATES RESTRICTED TO RELATIVES KNOWN TO BE MUTATION POSITIVE
—Unselected Jewish breast cancer patients from NY, 67 BRCA1, 37 BRCA2[49] 21% 46% 2% 12%    
MENDELIAN RETROSPECTIVE LIKELIHOOD APPROACH
—U.S.-based through the Cancer Genetics Network, most counseling clinic-based, although smaller number population-based, 238 BRCA1, 143 BRCA2[101]   40%   22%    

Cancer Risk in Individuals Who Test Negative for a Known Familial BRCA1/2 Mutation

There is conflicting evidence as to the residual familial risk among women who test negative for the BRCA1/BRCA2 mutation segregating in the family. Based on prospective evaluation of 353 women who tested negative for the BRCA1 mutation segregating in the family, five incident breast cancers occurred during more than 6,000 person-years of observation, for a lifetime risk of 6.8%.[121] A report that the risk may be as high as five-fold in women who tested negative for the BRCA1 or BRCA2 mutation in the family [124] was followed by numerous letters to the editor suggesting that ascertainment biases account for much of this observed excess risk.[125,126,127,128,129] Three additional analyses have suggested an approximate 1.5-fold to 2-fold excess risk.[129,130,131] Several studies have involved retrospective analyses; all studies have been based on small observed numbers of cases and have been of uncertain statistical and clinical significance. No cases of ovarian cancer have been reported in these studies.[129] Additional prospective analyses will be required to determine whether women from BRCA1/BRCA2 families who test negative for the identified mutation are at the general-population risk for breast cancer and require differential clinical management.[129]

Breast and Ovarian Cancer Risk in Breast Cancer Families Without Detectable BRCA1/2 Mutations

Most families with site-specific breast cancer test negative for BRCA1/2 and have no features consistent with Cowden syndrome or Li-Fraumeni syndrome.[29] Three studies using population-based and clinic-based approaches have demonstrated no increased risk of ovarian cancer in such families. Although ovarian cancer risk was not increased, breast cancer risk remained elevated.[115,132,133]

Population Estimates of the Likelihood of Having a BRCA1 or BRCA2 Mutation

Statistics regarding the percentage of women found to be BRCA mutation carriers among samples of women and men with a variety of personal cancer histories regardless of family history are provided below. These data can help determine who might best benefit from a referral for cancer genetic counseling and consideration of genetic testing, but cannot replace a personalized risk assessment, which might indicate a higher or lower mutation likelihood based on family history characteristics.

Among non-Ashkenazi Jewish individuals (likelihood of having any BRCA mutation):

  • General non-Ashkenazi Jewish population: 1 in 500 (0.2%).[134]
  • Women with breast cancer (all ages): 1 in 50 (2%).[135]
  • Women with breast cancer (younger than 40 years): 1 in 11 (9%).[136]
  • Men with breast cancer (regardless of age): 1 in 20 (5%).[137]
  • Women with ovarian cancer (all ages): 1 in 10 (10%).[48,138]

Among Ashkenazi Jewish individuals (likelihood of having one of three founder mutations):

  • General Ashkenazi Jewish population: 1 in 40 (2.5%).[52]
  • Women with breast cancer (all ages): 1 in 10 (10%).[49]
  • Women with breast cancer (younger than 40 years): 1 in 3 (30% – 35%).[49,139,140]
  • Men with breast cancer (regardless of age): 1 in 5 (19%).[141]
  • Women with ovarian cancer or primary peritoneal cancer (all ages): 1 in 3 (36% – 41%).[95,142,143]

Role of BRCA1 and BRCA2 in Sporadic Cancer

Given that germline mutations in BRCA1 or BRCA2 lead to a very high probability of developing breast and/or ovarian cancer, it was a natural assumption that these genes would also be involved in the development of the more common nonhereditary forms of the disease. Although somatic mutations in BRCA1 and BRCA2 are not common in sporadic breast and ovarian cancer tumors,[144,145,146,147] there is increasing evidence that downregulation of BRCA1 protein expression may play a role in these tumor types. Compared with normal breast epithelium, many breast cancers have low levels of the BRCA1 mRNA, which may result from hypermethylation of the gene promoter.[148,149,150] Similar findings have not been reported for BRCA2 mutations, although the BRCA2 locus on chromosome 13q is the target of frequent loss of heterozygosity (LOH) in breast cancer.[151,152] Approximately 10% to 15% of sporadic breast cancers appear to have BRCA1 promoter hypermethylation, and even more have downregulation of BRCA1 by other mechanisms. Basal-type breast cancers (ER negative, progesterone receptor negative, human epidermal growth factor receptor 2 [HER2] negative, cytokeratin 5/6 positive), more commonly have BRCA1 dysregulation than other tumor types.[153,154,155] Loss of BRCA1 or BRCA2 protein expression is more common in ovarian cancer than in breast cancer,[156] and downregulation of BRCA1 is associated with enhanced sensitivity to cisplatin and improved survival in this disease.[157,158] Targeted therapies are being developed for tumors with loss of BRCA1 or BRCA2 protein expression.[159]

Genotype-Phenotype Correlations

Some genotype-phenotype correlations have been identified in both BRCA1 and BRCA2 mutation families. In 25 families with BRCA2 mutations, an ovarian cancer cluster region was identified in exon 11 bordered by nucleotides 3,035 and 6,629.[11,91] This is the region of the gene containing the BRC repeats, which have been shown to specifically interact with RAD51. A study of 164 families with BRCA2 mutations collected by the Breast Cancer Linkage Consortium confirmed the initial finding. Mutations within the ovarian cancer cluster region were associated with an increased risk of ovarian cancer and a decreased risk of breast cancer in comparison to families with mutations on either side of this region.[97] In addition, a study of 356 families with protein-truncating BRCA1 mutations collected by the Breast Cancer Linkage Consortium reported breast cancer risk to be lower with mutations in the central region (nucleotides 2,401-4,190) compared with surrounding regions. Ovarian cancer risk was significantly reduced with mutations 3' to nucleotide 4,191.[160] These observations have generally been confirmed in subsequent studies.[99,100,161] Studies in Ashkenazim, in whom substantial numbers of families with the same mutation can be studied, have also found higher rates of ovarian cancer in carriers of the BRCA1:185delAG mutation, in the 5' end of BRCA1, compared with carriers of the BRCA1:5382insC mutation in the 3' end of the gene.[98,162] The risk of breast cancer, particularly bilateral breast cancer, and the occurrence of both breast and ovarian cancer in the same individual, however, appear to be higher in BRCA1:5382insC mutation carriers compared with carriers of BRCA1:185delAG and BRCA2:6174delT mutations. Ovarian cancer risk is considerably higher in BRCA1 mutation carriers, and it is uncommon before age 45 in BRCA2:6174delT mutation carriers.[98,162] None of the studies have had sufficient numbers of mutation-positive individuals to make definitive conclusions, and the findings are probably not sufficiently established to use in individual risk assessment and management.

Pathology/Prognosis of Breast Cancer

BRCA1

Pathology

Several studies evaluating pathologic patterns seen in BRCA1-associated breast cancers have suggested an association with adverse pathologic and biologic features. These findings include higher than expected frequencies of medullary histology, high histologic grade, areas of necrosis, aneuploidy, high S-phase fraction, high mitotic index, and frequent TP53 mutations.[163,164,165,166,167,168,169,170,171,172] Additionally, the triple-negative breast cancer phenotype (i.e. negative for ER, progesterone receptor [PR], and HER2), which also carries an adverse prognosis, accounts for 80% to 90% of BRCA1-associated breast cancers.[167,173,174,175] A study of 54 women with triple-negative breast cancer aged 40 years or younger, who were not considered candidates for BRCA testing because of the lack of a strong family history, showed five with BRCA1 mutations and one with a BRCA2 mutation (11% mutation prevalence).[176]

There is considerable, but not complete, overlap between the triple-negative and basal-like subtype cancers, both of which are more common in BRCA1-associated breast cancer.[177,178]

It has been hypothesized that many BRCA1 tumors are derived from the basal epithelial layer of cells of the normal mammary gland, which account for 3% to 15% of unselected invasive ductal cancers. If the basal epithelial cells of the breast represent the breast stem cells, the regulatory role suggested for wild-type BRCA1 may partly explain the aggressive phenotype of BRCA1-associated breast cancer when BRCA1 function is damaged.[179] Further studies are needed to fully appreciate the significance of this subtype of breast cancer within the hereditary syndromes.

The most accurate method for identifying basal-like breast cancers is through gene expression studies, which have been used to classify breast cancers into biologically- and clinically-meaningful groups.[174,180,181] This technology has also been shown to correctly differentiate BRCA1- and BRCA2-associated tumors from sporadic tumors in a high proportion of cases.[182,183,184] Notably, among a set of breast tumors studied by gene expression array to determine molecular phenotype, all tumors with BRCA1 alterations fell within the basal tumor subtype;[174] however, this technology is not in routine use due to its high cost. Instead, immunohistochemical markers of basal epithelium have been proposed to identify basal-like breast cancers, which are typically negative for ER, progesterone receptor, and HER2, and stain positive for cytokeratin 5/6, or EGFR.[185,186,187,188] Based on these methods to measure protein expression, a number of studies have shown that the majority of BRCA1-associated breast cancers are positive for basal epithelial markers.[167,175,187]

There is growing evidence that preinvasive lesions are a component of the BRCA phenotype. The Breast Cancer Linkage Consortium initially reported a relative lack of an in situ component in BRCA1-associated breast cancers,[164] also seen in two subsequent studies of BRCA1/2 carriers.[189,190] However, another study reported a similar prevalence of in situ cancers in BRCA1/2 carriers to that previously reported in studies of invasive breast cancer patients.[191] A retrospective study of breast cancer cases in a high-risk clinic found similar rates of preinvasive lesions, particularly DCIS, among 73 BRCA-associated breast cancers and 146 mutation-negative cases.[192,193] A study of Ashkenazi Jewish women, stratified by whether they were referred to a high-risk clinic or were unselected, showed similar prevalence of ductal carcinoma in situ (DCIS) and invasive breast cancers in referred patients compared with one-third lower DCIS cases among unselected subjects.[194] Similarly, data about the prevalence of hyperplastic lesions have been inconsistent, with reports of increased[195,196] and decreased prevalence.[190]

Overall evidence suggests DCIS is part of the BRCA1/BRCA2 spectrum; however, the prevalence of mutations in DCIS patients, unselected for family history, is less than 5%.[191,194]

Prognosis

The distinct features of BRCA1-associated breast tumors, as outlined above, are also important in prognosis. In addition, there appears to be accelerated growth in BRCA1-associated breast cancer, which is suggested by high-proliferation indices and absence of the expected correlation of tumor size with lymph node status.[190,197] These pathological features are associated with a worse prognosis in breast cancer, and early studies suggested that BRCA1 mutation carriers with breast cancer may have a poorer prognosis compared with sporadic cases.[169,198,199] These studies particularly noted an increase in ipsilateral and contralateral second primary breast cancers in BRCA1 mutation carriers.[200,201] A retrospective cohort study of 496 Ashkenazi Jewish breast cancer patients from two centers compared the relative survival among 56 BRCA1/2 mutation carriers followed for a median of 116 months. BRCA1 mutations were independently associated with worse disease-specific survival. The poorer prognosis was not observed in women who received chemotherapy.[202] A large population-based study of incident cases of breast cancer among women in Israel failed to find a difference in overall survival for carriers of BRCA1 founder mutations (n = 76) compared with noncarriers (n = 1,189).[203] Similar findings were seen in a European cohort with no differences in disease-free survival in BRCA1-associated breast cancers.[204]

In summary, BRCA1-associated tumors appear to have a prognosis similar to sporadic tumors despite having clinical, histopathologic, and molecular features, which indicate a more aggressive phenotype. BRCA1 mutation carriers who do not receive chemotherapy may have a worse prognosis. However, because most BRCA1-associated breast cancers are triple negative, they are usually treated with adjuvant chemotherapy. Work is ongoing to determine if BRCA1-associated breast cancers should receive different therapy than sporadic tumors. Refer to the Role of BRCA1 and BRCA2 in response to chemotherapy section for more information.

BRCA2

Pathology

The phenotype for BRCA2-related tumors appears to be more heterogeneous and is less well-characterized than that of BRCA1, although they are generally positive for ER and PR.[164,168,205] A report from Iceland found less tubule formation, more nuclear pleomorphism, and higher mitotic rates in BRCA2-related tumors compared with sporadic controls; however, a single BRCA2 founder mutation (999del5) accounts for nearly all hereditary breast cancer in this population, thus limiting the generalizability of this observation.[206] A large case series from North America and Europe described a greater proportion of BRCA2-associated tumors with continuous pushing margins, fewer tubules and lower mitotic counts.[207] Other reports suggest that BRCA2 related tumors include an excess of lobular and tubulolobular histology.[166,168] In summary, histologic characteristics associated with BRCA2 mutations have been inconsistent.

Prognosis

Studies of the prognosis of BRCA2 associated breast cancer have not shown substantial differences in comparison with sporadic breast cancer.[203,204,208,209]

Pathology/Prognosis of Ovarian Cancer

Pathology

Ovarian cancer arising in women with BRCA1 and BRCA2 mutations is more likely to be invasive serous adenocarcinoma, and less likely to be mucinous or borderline.[210,211,212] Fallopian tube cancer and papillary serous carcinoma of the peritoneum are also part of the spectrum of BRCA-associated disease.[143,213] Approximately 60% of sporadic ovarian cancers have serous histology, but a survey of all published data shows that 94% of BRCA1 related ovarian cancers have this type of histology.[148] Serous carcinoma was also found to be the predominant histologic subtype of intraperitoneal carcinoma among BRCA1/2 carriers in a Dutch case-control study.[214] Both primary ovarian carcinomas and primary peritoneal carcinomas have a higher incidence of somatic TP53 mutations and exhibit relatively aggressive features, including higher grade and p53 overexpression.[210,215] The histopathologic profile of BRCA2 related ovarian cancer has not been well defined. The finding of differential expression of genes in BRCA1, BRCA2, and sporadic ovarian cancer, using DNA microarray technology suggests distinct molecular pathways of carcinogenesis, which may ultimately distinguish them histologically.[216]

There are now several lines of evidence indicating that primary fallopian tube cancer should be considered a part of the BRCA1/2 phenotype. Histopathologic examination of fallopian tubes removed prophylactically from women with a hereditary predisposition to ovarian cancer show dysplastic and hyperplastic lesions that are accompanied by changes in cell-cycle and apoptosis-related proteins, suggesting a premalignant phenotype.[217,218] A retrospective review of 29 Ashkenazi Jewish patients with primary fallopian tube tumors identified germlineBRCA mutations in 17%.[143]

Prognosis

Despite generally poor prognostic factors, several studies have found an improved survival among ovarian cancer patients with BRCA mutations.[216,219,220,221,222,223,224] A nationwide, population-based case-control study in Israel found 3-year survival rates to be significantly better for ovarian cancer patients with BRCA founder mutations, compared with controls.[220] Five-year follow-up in the same cohort showed improved survival for carriers of both BRCA1 and BRCA2 mutations (54 months) versus noncarriers (38 months), which was most pronounced for women with stages III and IV ovarian cancer and for women with high-grade tumors.[225] In a U.S. study of Ashkenazi Jewish women with ovarian cancer, those with BRCA mutations had a longer median time to recurrence and an overall improved survival, compared with both Ashkenazi Jewish women with ovarian cancer who did not have a BRCA mutation and two large groups of advanced-stage ovarian cancer clinical trial patients.[223] In a retrospective, U.S., hospital-based study, BRCA Ashkenazi heterozygotes had a better response to platinum-based chemotherapy, as measured by response to primary therapy, disease-free survival, and overall survival, compared with sporadic cases.[221] A U.S. population-based study showed improvement in overall survival in BRCA2, but not in BRCA1, carriers.[226] However, the study included only 12 BRCA2 mutation carriers and 20 BRCA1 mutation carriers. A study in Japanese patients found a survival advantage in stage III BRCA1-associated ovarian cancers treated with cisplatin regimens compared with nonhereditary cancers treated in a similar manner.[222]

In contrast, several studies have not found improved overall survival among ovarian cancer patients with BRCA mutations.[198,227,228,229] A population-based study from Sweden noted an initial survival advantage in BRCA1-associated cases, but this advantage did not persist after 3 or 4 years.[198] Similarly, a case-control study from the Netherlands found an improvement in short-term (up to 5 years) survival among women with familial ovarian cancer compared to sporadic controls, but no difference in longer-term survival.[227] A study from the United Kingdom found a worse survival rate in ovarian cancer patients with a family history of ovarian cancer, whether or not they had a BRCA mutation, compared with sporadic controls.[228] Finally, a case-control study at the University of Iowa failed to find any survival advantage for women with BRCA1 inactivation, whether by germline mutation, somatic mutation, or BRCA1 promoter silencing.[229] In this study, however, cases (women with BRCA1 inactivation) were matched to controls on several variables, including tumor grade and p53 status, thus possibly minimizing any differences between the two groups.

There are compelling data to show improved survival in Ashkenazi Jewish ovarian cancer patients with BRCA1 or BRCA2 founder mutations; however, further large studies in other populations with appropriate controls are needed to determine whether this survival advantage applies more broadly to all BRCA1- or BRCA2-related ovarian cancers.

Other Rare Breast and Ovarian Cancer-Associated Syndromes

Li-Fraumeni syndrome

Breast cancer is also a component of the rare Li-Fraumeni syndrome (LFS) (OMIM), in which germline mutations of the TP53 gene (OMIM) on chromosome 17p have been documented.[230] This syndrome is characterized by premenopausal breast cancer in combination with childhood sarcoma, brain tumors, leukemia, and adrenocortical carcinoma.[231,232] Tumors in LFS families tend to occur in childhood and early adulthood, and often present as multiple primaries in the same individual. Evidence supports a genotype-phenotype correlation, with an association of the location of the mutation, the kind of cancer that develops, and the age of onset.[233] Brain and adrenal gland tumors were associated with specific sites of missense mutations. Age at onset of breast cancer was 34.6 years in families with a TP53 mutation compared with 42.5 years in those families without a mutation. A germline mutation in the TP53 gene has been identified in more than 50% of families exhibiting this syndrome, and inheritance is autosomal dominant, with a penetrance of at least 50% by age 50 years.

The prevalence of germline mutations among 525 samples submitted to City of Hope laboratories for clinical TP53 testing was determined. TP53 mutations were identified in 17% (n = 91) of the samples. All families with a TP53 mutation had at least one family member with a sarcoma, breast cancer, brain cancer, or adrenocortical cancer (core cancers). In addition, all eight individuals with a choroid plexus tumor had a TP53 mutation, as did 14 of the 21 individuals with childhood adrenocortical cancer. In the absence of a family history of core cancers other than breast cancer, no TP53 mutations were seen in women aged 30 to 49 years who had breast cancer. One TP53 mutation (7%) was seen in 14 women younger than 30 years who had breast cancer and no family history of cancer.[234]

Located on chromosome 17p, TP53 encodes a 53kd nuclear phosphoprotein that binds DNA sequences and functions as a negative regulator of cell growth and proliferation in the setting of DNA damage. It is also an active component of programmed cell death.[235] Inactivation of the TP53 gene or disruption of the protein product is thought to allow the persistence of damaged DNA and the possible development of malignant cells.[232] Evidence also exists that patients treated for a TP53-related tumor with chemotherapy or radiation therapy may be at risk of a treatment-related second malignancy. Germline mutations in TP53 are thought to account for fewer than 1% of breast cancer cases.[236]

Cowden syndrome

One of the more than 50 cancer-related genodermatoses, Cowden syndrome (OMIM) is characterized by multiple hamartomas, an excess of breast cancer, gastrointestinal malignancies, endometrial cancer, and thyroid disease, both benign and malignant.[237,238] Lifetime estimates for breast cancer among women with Cowden syndrome range from 25% to 50%. As in other forms of hereditary breast cancer, onset is often at a young age and may be bilateral.[239] Skin manifestations include multiple trichilemmomas, oral fibromas and papillomas, and acral, palmar, and plantar keratoses. History or observation of the characteristic skin features raises a suspicion of Cowden syndrome. Central nervous system manifestations include macrocephaly, developmental delay, and dysplastic gangliocytomas of the cerebellum.[240,241] Germline mutations in PTEN (OMIM), a protein tyrosine phosphatase with homology to tensin, located on chromosome 10q23, are responsible for this syndrome. Loss of heterozygosity at the PTEN locus observed in a high proportion of related cancers suggests that PTEN functions as a tumor suppressor gene. Its defined enzymatic function indicates a role in maintenance of the control of cell proliferation.[242] Disruption of PTEN appears to occur late in tumorigenesis and may act as a regulatory molecule of cytoskeletal function. Although PTEN mutations, which are estimated to occur in 1 in 200,000 individuals,[238] account for a small fraction of hereditary breast cancer, the characterization of PTEN function will provide valuable insights into the signal pathway and the maintenance of normal cell physiology.[238,243] (Refer to the PDQ summary Genetics of Colorectal Cancer Major Genes section for more information on Cowden syndrome.)

Peutz-Jeghers syndrome

Peutz-Jeghers syndrome (PJS) (OMIM) is an early-onset autosomal dominant disorder characterized by melanocytic macules on the lips, perioral, and buccal regions, and multiple gastrointestinal polyps, both hamartomatous and adenomatous.[244,245,246] Mutations in the STK11 gene (OMIM) at chromosome 19p13.3, which appears to function as a tumor suppressor gene,[247] have been identified as one cause of PJS.[248,249] Germline mutations in STK11, also known as LKB1, have been reported and appear to be responsible for about 50% of the cases of PJS.[248,249,250,251,252,253] A large series of 419 patients had a cumulative incidence of cancer of 85% by age 70 years, commonly affecting the GI tract. In addition, the cumulative risk of breast cancer was 31% by age 60 years; only two ovarian cancers were seen in this series.[254] Elevated cancer risks have also been seen in smaller series and a meta-analysis, including a higher risk of sex cord stromal tumors of the ovary.[255,256,257,258,259]

References:

1. Phipps RF, Perry PM: Familial breast cancer. Postgrad Med J 64 (757): 847-9, 1988.
2. Sellers TA, Potter JD, Rich SS, et al.: Familial clustering of breast and prostate cancers and risk of postmenopausal breast cancer. J Natl Cancer Inst 86 (24): 1860-5, 1994.
3. Newman B, Austin MA, Lee M, et al.: Inheritance of human breast cancer: evidence for autosomal dominant transmission in high-risk families. Proceedings of the National Academy of Sciences 85(9): 3044-3048, 1988.
4. Hall JM, Lee MK, Newman B, et al.: Linkage of early-onset familial breast cancer to chromosome 17q21. Science 250 (4988): 1684-9, 1990.
5. Narod SA, Feunteun J, Lynch HT, et al.: Familial breast-ovarian cancer locus on chromosome 17q12-q23. Lancet 338 (8759): 82-3, 1991.
6. Brose MS, Rebbeck TR, Calzone KA, et al.: Cancer risk estimates for BRCA1 mutation carriers identified in a risk evaluation program. J Natl Cancer Inst 94 (18): 1365-72, 2002.
7. Thompson D, Easton DF; Breast Cancer Linkage Consortium.: Cancer Incidence in BRCA1 mutation carriers. J Natl Cancer Inst 94 (18): 1358-65, 2002.
8. Risch HA, McLaughlin JR, Cole DE, et al.: Population BRCA1 and BRCA2 mutation frequencies and cancer penetrances: a kin-cohort study in Ontario, Canada. J Natl Cancer Inst 98 (23): 1694-706, 2006.
9. Tai YC, Domchek S, Parmigiani G, et al.: Breast cancer risk among male BRCA1 and BRCA2 mutation carriers. J Natl Cancer Inst 99 (23): 1811-4, 2007.
10. Wooster R, Neuhausen SL, Mangion J, et al.: Localization of a breast cancer susceptibility gene, BRCA2, to chromosome 13q12-13. Science 265 (5181): 2088-90, 1994.
11. Gayther SA, Mangion J, Russell P, et al.: Variation of risks of breast and ovarian cancer associated with different germline mutations of the BRCA2 gene. Nat Genet 15 (1): 103-5, 1997.
12. Cancer risks in BRCA2 mutation carriers. The Breast Cancer Linkage Consortium. J Natl Cancer Inst 91 (15): 1310-6, 1999.
13. Liede A, Karlan BY, Narod SA: Cancer risks for male carriers of germline mutations in BRCA1 or BRCA2: a review of the literature. J Clin Oncol 22 (4): 735-42, 2004.
14. Tonin P, Weber B, Offit K, et al.: Frequency of recurrent BRCA1 and BRCA2 mutations in Ashkenazi Jewish breast cancer families. Nat Med 2 (11): 1179-83, 1996.
15. Easton DF, Bishop DT, Ford D, et al.: Genetic linkage analysis in familial breast and ovarian cancer: results from 214 families. The Breast Cancer Linkage Consortium. Am J Hum Genet 52 (4): 678-701, 1993.
16. Smith SA, Easton DF, Evans DG, et al.: Allele losses in the region 17q12-21 in familial breast and ovarian cancer involve the wild-type chromosome. Nat Genet 2 (2): 128-31, 1992.
17. Collins N, McManus R, Wooster R, et al.: Consistent loss of the wild type allele in breast cancers from a family linked to the BRCA2 gene on chromosome 13q12-13. Oncogene 10 (8): 1673-5, 1995.
18. Gudmundsdottir K, Ashworth A: The roles of BRCA1 and BRCA2 and associated proteins in the maintenance of genomic stability. Oncogene 25 (43): 5864-74, 2006.
19. Mullan PB, Quinn JE, Harkin DP: The role of BRCA1 in transcriptional regulation and cell cycle control. Oncogene 25 (43): 5854-63, 2006.
20. An Open Access On-Line Breast Cancer Mutation Data Base. Bethesda, Md: National Human Genome Research Institute, 2002. Available online. Last accessed March 8, 2007.
21. Ford D, Easton DF, Peto J: Estimates of the gene frequency of BRCA1 and its contribution to breast and ovarian cancer incidence. Am J Hum Genet 57 (6): 1457-62, 1995.
22. Whittemore AS, Gong G, John EM, et al.: Prevalence of BRCA1 mutation carriers among U.S. non-Hispanic Whites. Cancer Epidemiol Biomarkers Prev 13 (12): 2078-83, 2004.
23. Eng C, Brody LC, Wagner TM, et al.: Interpreting epidemiological research: blinded comparison of methods used to estimate the prevalence of inherited mutations in BRCA1. J Med Genet 38 (12): 824-33, 2001.
24. Unger MA, Nathanson KL, Calzone K, et al.: Screening for genomic rearrangements in families with breast and ovarian cancer identifies BRCA1 mutations previously missed by conformation-sensitive gel electrophoresis or sequencing. Am J Hum Genet 67 (4): 841-50, 2000.
25. Walsh T, Casadei S, Coats KH, et al.: Spectrum of mutations in BRCA1, BRCA2, CHEK2, and TP53 in families at high risk of breast cancer. JAMA 295 (12): 1379-88, 2006.
26. Palma MD, Domchek SM, Stopfer J, et al.: The relative contribution of point mutations and genomic rearrangements in BRCA1 and BRCA2 in high-risk breast cancer families. Cancer Res 68 (17): 7006-14, 2008.
27. Plon SE, Eccles DM, Easton D, et al.: Sequence variant classification and reporting: recommendations for improving the interpretation of cancer susceptibility genetic test results. Hum Mutat 29 (11): 1282-91, 2008.
28. Nanda R, Schumm LP, Cummings S, et al.: Genetic testing in an ethnically diverse cohort of high-risk women: a comparative analysis of BRCA1 and BRCA2 mutations in American families of European and African ancestry. JAMA 294 (15): 1925-33, 2005.
29. Frank TS, Deffenbaugh AM, Reid JE, et al.: Clinical characteristics of individuals with germline mutations in BRCA1 and BRCA2: analysis of 10,000 individuals. J Clin Oncol 20 (6): 1480-90, 2002.
30. Hall MJ, Reid JE, Burbidge LA, et al.: BRCA1 and BRCA2 mutations in women of different ethnicities undergoing testing for hereditary breast-ovarian cancer. Cancer 115 (10): 2222-33, 2009.
31. Goldgar DE, Easton DF, Deffenbaugh AM, et al.: Integrated evaluation of DNA sequence variants of unknown clinical significance: application to BRCA1 and BRCA2. Am J Hum Genet 75 (4): 535-44, 2004.
32. Thompson D, Easton DF, Goldgar DE: A full-likelihood method for the evaluation of causality of sequence variants from family data. Am J Hum Genet 73 (3): 652-5, 2003.
33. Spearman AD, Sweet K, Zhou XP, et al.: Clinically applicable models to characterize BRCA1 and BRCA2 variants of uncertain significance. J Clin Oncol 26 (33): 5393-400, 2008.
34. Gómez García EB, Oosterwijk JC, Timmermans M, et al.: A method to assess the clinical significance of unclassified variants in the BRCA1 and BRCA2 genes based on cancer family history. Breast Cancer Res 11 (1): R8, 2009.
35. Goldgar DE, Easton DF, Byrnes GB, et al.: Genetic evidence and integration of various data sources for classifying uncertain variants into a single model. Hum Mutat 29 (11): 1265-72, 2008.
36. Fleming MA, Potter JD, Ramirez CJ, et al.: Understanding missense mutations in the BRCA1 gene: an evolutionary approach. Proc Natl Acad Sci U S A 100 (3): 1151-6, 2003.
37. Tavtigian SV, Deffenbaugh AM, Yin L, et al.: Comprehensive statistical study of 452 BRCA1 missense substitutions with classification of eight recurrent substitutions as neutral. J Med Genet 43 (4): 295-305, 2006.
38. Mirkovic N, Marti-Renom MA, Weber BL, et al.: Structure-based assessment of missense mutations in human BRCA1: implications for breast and ovarian cancer predisposition. Cancer Res 64 (11): 3790-7, 2004.
39. Abkevich V, Zharkikh A, Deffenbaugh AM, et al.: Analysis of missense variation in human BRCA1 in the context of interspecific sequence variation. J Med Genet 41 (7): 492-507, 2004.
40. Couch FJ, Rasmussen LJ, Hofstra R, et al.: Assessment of functional effects of unclassified genetic variants. Hum Mutat 29 (11): 1314-26, 2008.
41. Chenevix-Trench G, Healey S, Lakhani S, et al.: Genetic and histopathologic evaluation of BRCA1 and BRCA2 DNA sequence variants of unknown clinical significance. Cancer Res 66 (4): 2019-27, 2006.
42. Ostrow KL, McGuire V, Whittemore AS, et al.: The effects of BRCA1 missense variants V1804D and M1628T on transcriptional activity. Cancer Genet Cytogenet 153 (2): 177-80, 2004.
43. Wu K, Hinson SR, Ohashi A, et al.: Functional evaluation and cancer risk assessment of BRCA2 unclassified variants. Cancer Res 65 (2): 417-26, 2005.
44. John EM, Miron A, Gong G, et al.: Prevalence of pathogenic BRCA1 mutation carriers in 5 US racial/ethnic groups. JAMA 298 (24): 2869-76, 2007.
45. Malone KE, Daling JR, Doody DR, et al.: Prevalence and predictors of BRCA1 and BRCA2 mutations in a population-based study of breast cancer in white and black American women ages 35 to 64 years. Cancer Res 66 (16): 8297-308, 2006.
46. Malone KE, Daling JR, Thompson JD, et al.: BRCA1 mutations and breast cancer in the general population: analyses in women before age 35 years and in women before age 45 years with first-degree family history. JAMA 279 (12): 922-9, 1998.
47. Couch FJ, DeShano ML, Blackwood MA, et al.: BRCA1 mutations in women attending clinics that evaluate the risk of breast cancer. N Engl J Med 336 (20): 1409-15, 1997.
48. Risch HA, McLaughlin JR, Cole DE, et al.: Prevalence and penetrance of germline BRCA1 and BRCA2 mutations in a population series of 649 women with ovarian cancer. Am J Hum Genet 68 (3): 700-10, 2001.
49. King MC, Marks JH, Mandell JB, et al.: Breast and ovarian cancer risks due to inherited mutations in BRCA1 and BRCA2. Science 302 (5645): 643-6, 2003.
50. Struewing JP, Abeliovich D, Peretz T, et al.: The carrier frequency of the BRCA1 185delAG mutation is approximately 1 percent in Ashkenazi Jewish individuals. Nat Genet 11 (2): 198-200, 1995.
51. Oddoux C, Struewing JP, Clayton CM, et al.: The carrier frequency of the BRCA2 6174delT mutation among Ashkenazi Jewish individuals is approximately 1%. Nat Genet 14 (2): 188-90, 1996.
52. Struewing JP, Hartge P, Wacholder S, et al.: The risk of cancer associated with specific mutations of BRCA1 and BRCA2 among Ashkenazi Jews. N Engl J Med 336 (20): 1401-8, 1997.
53. Roa BB, Boyd AA, Volcik K, et al.: Ashkenazi Jewish population frequencies for common mutations in BRCA1 and BRCA2. Nat Genet 14 (2): 185-7, 1996.
54. Ellisen LW, Haber DA: Hereditary breast cancer. Annu Rev Med 49: 425-36, 1998.
55. Brody LC, Biesecker BB: Breast cancer susceptibility genes. BRCA1 and BRCA2. Medicine (Baltimore) 77 (3): 208-26, 1998.
56. Machado PM, Brandão RD, Cavaco BM, et al.: Screening for a BRCA2 rearrangement in high-risk breast/ovarian cancer families: evidence for a founder effect and analysis of the associated phenotypes. J Clin Oncol 25 (15): 2027-34, 2007.
57. Peelen T, van Vliet M, Petrij-Bosch A, et al.: A high proportion of novel mutations in BRCA1 with strong founder effects among Dutch and Belgian hereditary breast and ovarian cancer families. Am J Hum Genet 60 (5): 1041-9, 1997.
58. Thorlacius S, Olafsdottir G, Tryggvadottir L, et al.: A single BRCA2 mutation in male and female breast cancer families from Iceland with varied cancer phenotypes. Nat Genet 13 (1): 117-9, 1996.
59. Arason A, Jonasdottir A, Barkardottir RB, et al.: A population study of mutations and LOH at breast cancer gene loci in tumours from sister pairs: two recurrent mutations seem to account for all BRCA1/BRCA2 linked breast cancer in Iceland. J Med Genet 35 (6): 446-9, 1998.
60. Einbeigi Z, Bergman A, Kindblom LG, et al.: A founder mutation of the BRCA1 gene in Western Sweden associated with a high incidence of breast and ovarian cancer. Eur J Cancer 37 (15): 1904-9, 2001.
61. Shattuck-Eidens D, Oliphant A, McClure M, et al.: BRCA1 sequence analysis in women at high risk for susceptibility mutations. Risk factor analysis and implications for genetic testing. JAMA 278 (15): 1242-50, 1997.
62. Spiegelman D, Colditz GA, Hunter D, et al.: Validation of the Gail et al. model for predicting individual breast cancer risk. J Natl Cancer Inst 86 (8): 600-7, 1994.
63. Frank TS, Manley SA, Olopade OI, et al.: Sequence analysis of BRCA1 and BRCA2: correlation of mutations with family history and ovarian cancer risk. J Clin Oncol 16 (7): 2417-25, 1998.
64. Chang-Claude J, Dong J, Schmidt S, et al.: Using gene carrier probability to select high risk families for identifying germline mutations in breast cancer susceptibility genes. J Med Genet 35 (2): 116-21, 1998.
65. Couch FJ, Hartmann LC: BRCA1 testing--advances and retreats. JAMA 279 (12): 955-7, 1998.
66. Parmigiani G, Berry D, Aguilar O: Determining carrier probabilities for breast cancer-susceptibility genes BRCA1 and BRCA2. Am J Hum Genet 62 (1): 145-58, 1998.
67. Newman B, Mu H, Butler LM, et al.: Frequency of breast cancer attributable to BRCA1 in a population-based series of American women. JAMA 279 (12): 915-21, 1998.
68. Evans DG, Eccles DM, Rahman N, et al.: A new scoring system for the chances of identifying a BRCA1/2 mutation outperforms existing models including BRCAPRO. J Med Genet 41 (6): 474-80, 2004.
69. Apicella C, Dowty JG, Dite GS, et al.: Validation study of the LAMBDA model for predicting the BRCA1 or BRCA2 mutation carrier status of North American Ashkenazi Jewish women. Clin Genet 72 (2): 87-97, 2007.
70. Antoniou AC, Pharoah PP, Smith P, et al.: The BOADICEA model of genetic susceptibility to breast and ovarian cancer. Br J Cancer 91 (8): 1580-90, 2004.
71. Warner E, Foulkes W, Goodwin P, et al.: Prevalence and penetrance of BRCA1 and BRCA2 gene mutations in unselected Ashkenazi Jewish women with breast cancer. J Natl Cancer Inst 91 (14): 1241-7, 1999.
72. Prevalence and penetrance of BRCA1 and BRCA2 mutations in a population-based series of breast cancer cases. Anglian Breast Cancer Study Group. Br J Cancer 83 (10): 1301-8, 2000.
73. Euhus DM, Smith KC, Robinson L, et al.: Pretest prediction of BRCA1 or BRCA2 mutation by risk counselors and the computer model BRCAPRO. J Natl Cancer Inst 94 (11): 844-51, 2002.
74. de la Hoya M, Díez O, Pérez-Segura P, et al.: Pre-test prediction models of BRCA1 or BRCA2 mutation in breast/ovarian families attending familial cancer clinics. J Med Genet 40 (7): 503-10, 2003.
75. Berry DA, Parmigiani G, Sanchez J, et al.: Probability of carrying a mutation of breast-ovarian cancer gene BRCA1 based on family history. J Natl Cancer Inst 89 (3): 227-38, 1997.
76. Barcenas CH, Hosain GM, Arun B, et al.: Assessing BRCA carrier probabilities in extended families. J Clin Oncol 24 (3): 354-60, 2006.
77. Kang HH, Williams R, Leary J, et al.: Evaluation of models to predict BRCA germline mutations. Br J Cancer 95 (7): 914-20, 2006.
78. Antoniou AC, Hardy R, Walker L, et al.: Predicting the likelihood of carrying a BRCA1 or BRCA2 mutation: validation of BOADICEA, BRCAPRO, IBIS, Myriad and the Manchester scoring system using data from UK genetics clinics. J Med Genet 45 (7): 425-31, 2008.
79. Katki HA: Incorporating medical interventions into carrier probability estimation for genetic counseling. BMC Med Genet 8: 13, 2007.
80. Weitzel JN, Lagos VI, Cullinane CA, et al.: Limited family structure and BRCA gene mutation status in single cases of breast cancer. JAMA 297 (23): 2587-95, 2007.
81. Oros KK, Ghadirian P, Maugard CM, et al.: Application of BRCA1 and BRCA2 mutation carrier prediction models in breast and/or ovarian cancer families of French Canadian descent. Clin Genet 70 (4): 320-9, 2006.
82. Vogel KJ, Atchley DP, Erlichman J, et al.: BRCA1 and BRCA2 genetic testing in Hispanic patients: mutation prevalence and evaluation of the BRCAPRO risk assessment model. J Clin Oncol 25 (29): 4635-41, 2007.
83. Kurian AW, Gong GD, John EM, et al.: Performance of prediction models for BRCA mutation carriage in three racial/ethnic groups: findings from the Northern California Breast Cancer Family Registry. Cancer Epidemiol Biomarkers Prev 18 (4): 1084-91, 2009.
84. Kurian AW, Gong GD, Chun NM, et al.: Performance of BRCA1/2 mutation prediction models in Asian Americans. J Clin Oncol 26 (29): 4752-8, 2008.
85. Tyrer J, Duffy SW, Cuzick J: A breast cancer prediction model incorporating familial and personal risk factors. Stat Med 23 (7): 1111-30, 2004.
86. Ready KJ, Vogel KJ, Atchley DP, et al.: Accuracy of the BRCAPRO model among women with bilateral breast cancer. Cancer 115 (4): 725-30, 2009.
87. Huo D, Senie RT, Daly M, et al.: Prediction of BRCA Mutations Using the BRCAPRO Model in Clinic-Based African American, Hispanic, and Other Minority Families in the United States. J Clin Oncol 27 (8): 1184-90, 2009.
88. Ford D, Easton DF, Bishop DT, et al.: Risks of cancer in BRCA1-mutation carriers. Breast Cancer Linkage Consortium. Lancet 343 (8899): 692-5, 1994.
89. Easton DF, Ford D, Bishop DT: Breast and ovarian cancer incidence in BRCA1-mutation carriers. Breast Cancer Linkage Consortium. Am J Hum Genet 56 (1): 265-71, 1995.
90. Levy-Lahad E, Catane R, Eisenberg S, et al.: Founder BRCA1 and BRCA2 mutations in Ashkenazi Jews in Israel: frequency and differential penetrance in ovarian cancer and in breast-ovarian cancer families. Am J Hum Genet 60 (5): 1059-67, 1997.
91. Ford D, Easton DF, Stratton M, et al.: Genetic heterogeneity and penetrance analysis of the BRCA1 and BRCA2 genes in breast cancer families. The Breast Cancer Linkage Consortium. Am J Hum Genet 62 (3): 676-89, 1998.
92. Thorlacius S, Struewing JP, Hartge P, et al.: Population-based study of risk of breast cancer in carriers of BRCA2 mutation. Lancet 352 (9137): 1337-9, 1998.
93. Hopper JL, Southey MC, Dite GS, et al.: Population-based estimate of the average age-specific cumulative risk of breast cancer for a defined set of protein-truncating mutations in BRCA1 and BRCA2. Australian Breast Cancer Family Study. Cancer Epidemiol Biomarkers Prev 8 (9): 741-7, 1999.
94. Antoniou AC, Gayther SA, Stratton JF, et al.: Risk models for familial ovarian and breast cancer. Genet Epidemiol 18 (2): 173-90, 2000.
95. Moslehi R, Chu W, Karlan B, et al.: BRCA1 and BRCA2 mutation analysis of 208 Ashkenazi Jewish women with ovarian cancer. Am J Hum Genet 66 (4): 1259-72, 2000.
96. Satagopan JM, Offit K, Foulkes W, et al.: The lifetime risks of breast cancer in Ashkenazi Jewish carriers of BRCA1 and BRCA2 mutations. Cancer Epidemiol Biomarkers Prev 10 (5): 467-73, 2001.
97. Thompson D, Easton D; Breast Cancer Linkage Consortium.: Variation in cancer risks, by mutation position, in BRCA2 mutation carriers. Am J Hum Genet 68 (2): 410-9, 2001.
98. Satagopan JM, Boyd J, Kauff ND, et al.: Ovarian cancer risk in Ashkenazi Jewish carriers of BRCA1 and BRCA2 mutations. Clin Cancer Res 8 (12): 3776-81, 2002.
99. Antoniou A, Pharoah PD, Narod S, et al.: Average risks of breast and ovarian cancer associated with BRCA1 or BRCA2 mutations detected in case Series unselected for family history: a combined analysis of 22 studies. Am J Hum Genet 72 (5): 1117-30, 2003.
100. Scott CL, Jenkins MA, Southey MC, et al.: Average age-specific cumulative risk of breast cancer according to type and site of germline mutations in BRCA1 and BRCA2 estimated from multiple-case breast cancer families attending Australian family cancer clinics. Hum Genet 112 (5-6): 542-51, 2003.
101. Chen S, Iversen ES, Friebel T, et al.: Characterization of BRCA1 and BRCA2 mutations in a large United States sample. J Clin Oncol 24 (6): 863-71, 2006.
102. Thompson D, Szabo CI, Mangion J, et al.: Evaluation of linkage of breast cancer to the putative BRCA3 locus on chromosome 13q21 in 128 multiple case families from the Breast Cancer Linkage Consortium. Proc Natl Acad Sci U S A 99 (2): 827-31, 2002.
103. Edwards SM, Kote-Jarai Z, Meitz J, et al.: Two percent of men with early-onset prostate cancer harbor germline mutations in the BRCA2 gene. Am J Hum Genet 72 (1): 1-12, 2003.
104. Giusti RM, Rutter JL, Duray PH, et al.: A twofold increase in BRCA mutation related prostate cancer among Ashkenazi Israelis is not associated with distinctive histopathology. J Med Genet 40 (10): 787-92, 2003.
105. van Asperen CJ, Brohet RM, Meijers-Heijboer EJ, et al.: Cancer risks in BRCA2 families: estimates for sites other than breast and ovary. J Med Genet 42 (9): 711-9, 2005.
106. Anton-Culver H, Cohen PF, Gildea ME, et al.: Characteristics of BRCA1 mutations in a population-based case series of breast and ovarian cancer. Eur J Cancer 36 (10): 1200-8, 2000.
107. Peelen T, de Leeuw W, van Lent K, et al.: Genetic analysis of a breast-ovarian cancer family, with 7 cases of colorectal cancer linked to BRCA1, fails to support a role for BRCA1 in colorectal tumorigenesis. Int J Cancer 88 (5): 778-82, 2000.
108. Berman DB, Costalas J, Schultz DC, et al.: A common mutation in BRCA2 that predisposes to a variety of cancers is found in both Jewish Ashkenazi and non-Jewish individuals. Cancer Res 56 (15): 3409-14, 1996.
109. Aretini P, D'Andrea E, Pasini B, et al.: Different expressivity of BRCA1 and BRCA2: analysis of 179 Italian pedigrees with identified mutation. Breast Cancer Res Treat 81 (1): 71-9, 2003.
110. Kirchhoff T, Satagopan JM, Kauff ND, et al.: Frequency of BRCA1 and BRCA2 mutations in unselected Ashkenazi Jewish patients with colorectal cancer. J Natl Cancer Inst 96 (1): 68-70, 2004.
111. Niell BL, Rennert G, Bonner JD, et al.: BRCA1 and BRCA2 founder mutations and the risk of colorectal cancer. J Natl Cancer Inst 96 (1): 15-21, 2004.
112. Chen-Shtoyerman R, Figer A, Fidder HH, et al.: The frequency of the predominant Jewish mutations in BRCA1 and BRCA2 in unselected Ashkenazi colorectal cancer patients. Br J Cancer 84 (4): 475-7, 2001.
113. Chen S, Parmigiani G: Meta-analysis of BRCA1 and BRCA2 penetrance. J Clin Oncol 25 (11): 1329-33, 2007.
114. Metcalfe KA, Lynch HT, Ghadirian P, et al.: The risk of ovarian cancer after breast cancer in BRCA1 and BRCA2 carriers. Gynecol Oncol 96 (1): 222-6, 2005.
115. Lee JS, John EM, McGuire V, et al.: Breast and ovarian cancer in relatives of cancer patients, with and without BRCA mutations. Cancer Epidemiol Biomarkers Prev 15 (2): 359-63, 2006.
116. Simchoni S, Friedman E, Kaufman B, et al.: Familial clustering of site-specific cancer risks associated with BRCA1 and BRCA2 mutations in the Ashkenazi Jewish population. Proc Natl Acad Sci U S A 103 (10): 3770-4, 2006.
117. Gronwald J, Huzarski T, Byrski B, et al.: Cancer risks in first degree relatives of BRCA1 mutation carriers: effects of mutation and proband disease status. J Med Genet 43 (5): 424-8, 2006.
118. Wang WW, Spurdle AB, Kolachana P, et al.: A single nucleotide polymorphism in the 5' untranslated region of RAD51 and risk of cancer among BRCA1/2 mutation carriers. Cancer Epidemiol Biomarkers Prev 10 (9): 955-60, 2001.
119. Levy-Lahad E, Lahad A, Eisenberg S, et al.: A single nucleotide polymorphism in the RAD51 gene modifies cancer risk in BRCA2 but not BRCA1 carriers. Proc Natl Acad Sci U S A 98 (6): 3232-6, 2001.
120. Narod SA: Modifiers of risk of hereditary breast and ovarian cancer. Nat Rev Cancer 2 (2): 113-23, 2002.
121. Kramer JL, Velazquez IA, Chen BE, et al.: Prophylactic oophorectomy reduces breast cancer penetrance during prospective, long-term follow-up of BRCA1 mutation carriers. J Clin Oncol 23 (34): 8629-35, 2005.
122. Antoniou AC, Spurdle AB, Sinilnikova OM, et al.: Common breast cancer-predisposition alleles are associated with breast cancer risk in BRCA1 and BRCA2 mutation carriers. Am J Hum Genet 82 (4): 937-48, 2008.
123. Begg CB, Haile RW, Borg A, et al.: Variation of breast cancer risk among BRCA1/2 carriers. JAMA 299 (2): 194-201, 2008.
124. Smith A, Moran A, Boyd MC, et al.: Phenocopies in BRCA1 and BRCA2 families: evidence for modifier genes and implications for screening. J Med Genet 44 (1): 10-15, 2007.
125. Goldgar D, Venne V, Conner T, et al.: BRCA phenocopies or ascertainment bias? J Med Genet 44 (8): e86; author reply e88, 2007.
126. Eisinger F: Phenocopies: actual risk or self-fulfilling prophecy? J Med Genet 44 (8): e87; author reply e88, 2007.
127. Sasieni P: Phenocopies in families seen by cancer geneticists. J Med Genet 44 (6): e82, 2007.
128. Tilanus-Linthorst MM: No screening yet after a negative test for the family mutation. J Med Genet 44 (5): e79, 2007.
129. Katki HA, Gail MH, Greene MH: Breast-cancer risk in BRCA-mutation-negative women from BRCA-mutation-positive families. Lancet Oncol 8 (12): 1042-3, 2007.
130. Gronwald J, Cybulski C, Lubinski J, et al.: Phenocopies in breast cancer 1 (BRCA1) families: implications for genetic counselling. J Med Genet 44 (4): e76, 2007.
131. Rowan E, Poll A, Narod SA: A prospective study of breast cancer risk in relatives of BRCA1/BRCA2 mutation carriers. J Med Genet 44 (8): e89; author reply e88, 2007.
132. Kauff ND, Mitra N, Robson ME, et al.: Risk of ovarian cancer in BRCA1 and BRCA2 mutation-negative hereditary breast cancer families. J Natl Cancer Inst 97 (18): 1382-4, 2005.
133. Metcalfe KA, Finch A, Poll A, et al.: Breast cancer risks in women with a family history of breast or ovarian cancer who have tested negative for a BRCA1 or BRCA2 mutation. Br J Cancer 100 (2): 421-5, 2009.
134. Szabo CI, King MC: Population genetics of BRCA1 and BRCA2. Am J Hum Genet 60 (5): 1013-20, 1997.
135. Papelard H, de Bock GH, van Eijk R, et al.: Prevalence of BRCA1 in a hospital-based population of Dutch breast cancer patients. Br J Cancer 83 (6): 719-24, 2000.
136. Loman N, Johannsson O, Kristoffersson U, et al.: Family history of breast and ovarian cancers and BRCA1 and BRCA2 mutations in a population-based series of early-onset breast cancer. J Natl Cancer Inst 93 (16): 1215-23, 2001.
137. Basham VM, Lipscombe JM, Ward JM, et al.: BRCA1 and BRCA2 mutations in a population-based study of male breast cancer. Breast Cancer Res 4 (1): R2, 2002.
138. Rubin SC, Blackwood MA, Bandera C, et al.: BRCA1, BRCA2, and hereditary nonpolyposis colorectal cancer gene mutations in an unselected ovarian cancer population: relationship to family history and implications for genetic testing. Am J Obstet Gynecol 178 (4): 670-7, 1998.
139. Gershoni-Baruch R, Dagan E, Fried G, et al.: Significantly lower rates of BRCA1/BRCA2 founder mutations in Ashkenazi women with sporadic compared with familial early onset breast cancer. Eur J Cancer 36 (8): 983-6, 2000.
140. Hodgson SV, Heap E, Cameron J, et al.: Risk factors for detecting germline BRCA1 and BRCA2 founder mutations in Ashkenazi Jewish women with breast or ovarian cancer. J Med Genet 36 (5): 369-73, 1999.
141. Struewing JP, Coriaty ZM, Ron E, et al.: Founder BRCA1/2 mutations among male patients with breast cancer in Israel. Am J Hum Genet 65 (6): 1800-2, 1999.
142. Hirsh-Yechezkel G, Chetrit A, Lubin F, et al.: Population attributes affecting the prevalence of BRCA mutation carriers in epithelial ovarian cancer cases in Israel. Gynecol Oncol 89 (3): 494-8, 2003.
143. Levine DA, Argenta PA, Yee CJ, et al.: Fallopian tube and primary peritoneal carcinomas associated with BRCA mutations. J Clin Oncol 21 (22): 4222-7, 2003.
144. Futreal PA, Liu Q, Shattuck-Eidens D, et al.: BRCA1 mutations in primary breast and ovarian carcinomas. Science 266 (5182): 120-2, 1994.
145. Lancaster JM, Wooster R, Mangion J, et al.: BRCA2 mutations in primary breast and ovarian cancers. Nat Genet 13 (2): 238-40, 1996.
146. Miki Y, Katagiri T, Kasumi F, et al.: Mutation analysis in the BRCA2 gene in primary breast cancers. Nat Genet 13 (2): 245-7, 1996.
147. Teng DH, Bogden R, Mitchell J, et al.: Low incidence of BRCA2 mutations in breast carcinoma and other cancers. Nat Genet 13 (2): 241-4, 1996.
148. Berchuck A, Heron KA, Carney ME, et al.: Frequency of germline and somatic BRCA1 mutations in ovarian cancer. Clin Cancer Res 4 (10): 2433-7, 1998.
149. Thompson ME, Jensen RA, Obermiller PS, et al.: Decreased expression of BRCA1 accelerates growth and is often present during sporadic breast cancer progression. Nat Genet 9 (4): 444-50, 1995.
150. Dobrovic A, Simpfendorfer D: Methylation of the BRCA1 gene in sporadic breast cancer. Cancer Res 57 (16): 3347-50, 1997.
151. Cleton-Jansen AM, Collins N, Lakhani SR, et al.: Loss of heterozygosity in sporadic breast tumours at the BRCA2 locus on chromosome 13q12-q13. Br J Cancer 72 (5): 1241-4, 1995.
152. Hamann U, Herbold C, Costa S, et al.: Allelic imbalance on chromosome 13q: evidence for the involvement of BRCA2 and RB1 in sporadic breast cancer. Cancer Res 56 (9): 1988-90, 1996.
153. Birgisdottir V, Stefansson OA, Bodvarsdottir SK, et al.: Epigenetic silencing and deletion of the BRCA1 gene in sporadic breast cancer. Breast Cancer Res 8 (4): R38, 2006.
154. Turner NC, Reis-Filho JS, Russell AM, et al.: BRCA1 dysfunction in sporadic basal-like breast cancer. Oncogene 26 (14): 2126-32, 2007.
155. Rakha EA, El-Sheikh SE, Kandil MA, et al.: Expression of BRCA1 protein in breast cancer and its prognostic significance. Hum Pathol 39 (6): 857-65, 2008.
156. Hilton JL, Geisler JP, Rathe JA, et al.: Inactivation of BRCA1 and BRCA2 in ovarian cancer. J Natl Cancer Inst 94 (18): 1396-406, 2002.
157. Quinn JE, James CR, Stewart GE, et al.: BRCA1 mRNA expression levels predict for overall survival in ovarian cancer after chemotherapy. Clin Cancer Res 13 (24): 7413-20, 2007.
158. Geisler JP, Hatterman-Zogg MA, Rathe JA, et al.: Frequency of BRCA1 dysfunction in ovarian cancer. J Natl Cancer Inst 94 (1): 61-7, 2002.
159. Farmer H, McCabe N, Lord CJ, et al.: Targeting the DNA repair defect in BRCA mutant cells as a therapeutic strategy. Nature 434 (7035): 917-21, 2005.
160. Thompson D, Easton D; Breast Cancer Linkage Consortium.: Variation in BRCA1 cancer risks by mutation position. Cancer Epidemiol Biomarkers Prev 11 (4): 329-36, 2002.
161. Lubinski J, Phelan CM, Ghadirian P, et al.: Cancer variation associated with the position of the mutation in the BRCA2 gene. Fam Cancer 3 (1): 1-10, 2004.
162. Rennert G, Dishon S, Rennert HS, et al.: Differences in the characteristics of families with BRCA1 and BRCA2 mutations in Israel. Eur J Cancer Prev 14 (4): 357-61, 2005.
163. Eisinger F, Jacquemier J, Charpin C, et al.: Mutations at BRCA1: the medullary breast carcinoma revisited. Cancer Res 58 (8): 1588-92, 1998.
164. Pathology of familial breast cancer: differences between breast cancers in carriers of BRCA1 or BRCA2 mutations and sporadic cases. Breast Cancer Linkage Consortium. Lancet 349 (9064): 1505-10, 1997.
165. Lorenzo Bermejo J, Hemminki K: A population-based assessment of the clustering of breast cancer in families eligible for testing of BRCA1 and BRCA2 mutations. Ann Oncol 16 (2): 322-9, 2005.
166. Armes JE, Egan AJ, Southey MC, et al.: The histologic phenotypes of breast carcinoma occurring before age 40 years in women with and without BRCA1 or BRCA2 germline mutations: a population-based study. Cancer 83 (11): 2335-45, 1998.
167. Foulkes WD, Stefansson IM, Chappuis PO, et al.: Germline BRCA1 mutations and a basal epithelial phenotype in breast cancer. J Natl Cancer Inst 95 (19): 1482-5, 2003.
168. Marcus JN, Watson P, Page DL, et al.: Hereditary breast cancer: pathobiology, prognosis, and BRCA1 and BRCA2 gene linkage. Cancer 77 (4): 697-709, 1996.
169. Verhoog LC, Brekelmans CT, Seynaeve C, et al.: Survival and tumour characteristics of breast-cancer patients with germline mutations of BRCA1. Lancet 351 (9099): 316-21, 1998.
170. Møller P, Borg A, Evans DG, et al.: Survival in prospectively ascertained familial breast cancer: analysis of a series stratified by tumour characteristics, BRCA mutations and oophorectomy. Int J Cancer 101 (6): 555-9, 2002.
171. Veronesi A, de Giacomi C, Magri MD, et al.: Familial breast cancer: characteristics and outcome of BRCA 1-2 positive and negative cases. BMC Cancer 5: 70, 2005.
172. Manié E, Vincent-Salomon A, Lehmann-Che J, et al.: High frequency of TP53 mutation in BRCA1 and sporadic basal-like carcinomas but not in BRCA1 luminal breast tumors. Cancer Res 69 (2): 663-71, 2009.
173. Lakhani SR, Van De Vijver MJ, Jacquemier J, et al.: The pathology of familial breast cancer: predictive value of immunohistochemical markers estrogen receptor, progesterone receptor, HER-2, and p53 in patients with mutations in BRCA1 and BRCA2. J Clin Oncol 20 (9): 2310-8, 2002.
174. Sorlie T, Tibshirani R, Parker J, et al.: Repeated observation of breast tumor subtypes in independent gene expression data sets. Proc Natl Acad Sci U S A 100 (14): 8418-23, 2003.
175. Lakhani SR, Reis-Filho JS, Fulford L, et al.: Prediction of BRCA1 status in patients with breast cancer using estrogen receptor and basal phenotype. Clin Cancer Res 11 (14): 5175-80, 2005.
176. Young SR, Pilarski RT, Donenberg T, et al.: The prevalence of BRCA1 mutations among young women with triple-negative breast cancer. BMC Cancer 9: 86, 2009.
177. Anders C, Carey LA: Understanding and treating triple-negative breast cancer. Oncology (Williston Park) 22 (11): 1233-9; discussion 1239-40, 1243, 2008.
178. Atchley DP, Albarracin CT, Lopez A, et al.: Clinical and pathologic characteristics of patients with BRCA-positive and BRCA-negative breast cancer. J Clin Oncol 26 (26): 4282-8, 2008.
179. Foulkes WD: BRCA1 functions as a breast stem cell regulator. J Med Genet 41 (1): 1-5, 2004.
180. Perou CM, Sørlie T, Eisen MB, et al.: Molecular portraits of human breast tumours. Nature 406 (6797): 747-52, 2000.
181. Sørlie T, Perou CM, Tibshirani R, et al.: Gene expression patterns of breast carcinomas distinguish tumor subclasses with clinical implications. Proc Natl Acad Sci U S A 98 (19): 10869-74, 2001.
182. Hedenfalk I, Duggan D, Chen Y, et al.: Gene-expression profiles in hereditary breast cancer. N Engl J Med 344 (8): 539-48, 2001.
183. Wessels LF, van Welsem T, Hart AA, et al.: Molecular classification of breast carcinomas by comparative genomic hybridization: a specific somatic genetic profile for BRCA1 tumors. Cancer Res 62 (23): 7110-7, 2002.
184. Palacios J, Honrado E, Osorio A, et al.: Immunohistochemical characteristics defined by tissue microarray of hereditary breast cancer not attributable to BRCA1 or BRCA2 mutations: differences from breast carcinomas arising in BRCA1 and BRCA2 mutation carriers. Clin Cancer Res 9 (10 Pt 1): 3606-14, 2003.
185. Nielsen TO, Hsu FD, Jensen K, et al.: Immunohistochemical and clinical characterization of the basal-like subtype of invasive breast carcinoma. Clin Cancer Res 10 (16): 5367-74, 2004.
186. Palacios J, Honrado E, Osorio A, et al.: Phenotypic characterization of BRCA1 and BRCA2 tumors based in a tissue microarray study with 37 immunohistochemical markers. Breast Cancer Res Treat 90 (1): 5-14, 2005.
187. Laakso M, Loman N, Borg A, et al.: Cytokeratin 5/14-positive breast cancer: true basal phenotype confined to BRCA1 tumors. Mod Pathol 18 (10): 1321-8, 2005.
188. Cheang MC, Voduc D, Bajdik C, et al.: Basal-like breast cancer defined by five biomarkers has superior prognostic value than triple-negative phenotype. Clin Cancer Res 14 (5): 1368-76, 2008.
189. Hwang ES, McLennan JL, Moore DH, et al.: Ductal carcinoma in situ in BRCA mutation carriers. J Clin Oncol 25 (6): 642-7, 2007.
190. Adem C, Reynolds C, Soderberg CL, et al.: Pathologic characteristics of breast parenchyma in patients with hereditary breast carcinoma, including BRCA1 and BRCA2 mutation carriers. Cancer 97 (1): 1-11, 2003.
191. Claus EB, Petruzella S, Matloff E, et al.: Prevalence of BRCA1 and BRCA2 mutations in women diagnosed with ductal carcinoma in situ. JAMA 293 (8): 964-9, 2005.
192. Arun B, Vogel KJ, Lopez A, et al.: High prevalence of preinvasive lesions adjacent to BRCA1/2-associated breast cancers. Cancer Prev Res (Phila Pa) 2 (2): 122-7, 2009.
193. Garber JE: BRCA1/2-associated and sporadic breast cancers: fellow travelers or not? Cancer Prev Res (Phila Pa) 2 (2): 100-3, 2009.
194. Smith KL, Adank M, Kauff N, et al.: BRCA mutations in women with ductal carcinoma in situ. Clin Cancer Res 13 (14): 4306-10, 2007.
195. Hoogerbrugge N, Bult P, Bonenkamp JJ, et al.: Numerous high-risk epithelial lesions in familial breast cancer. Eur J Cancer 42 (15): 2492-8, 2006.
196. Kauff ND, Brogi E, Scheuer L, et al.: Epithelial lesions in prophylactic mastectomy specimens from women with BRCA mutations. Cancer 97 (7): 1601-8, 2003.
197. Foulkes WD, Metcalfe K, Hanna W, et al.: Disruption of the expected positive correlation between breast tumor size and lymph node status in BRCA1-related breast carcinoma. Cancer 98 (8): 1569-77, 2003.
198. Jóhannsson OT, Ranstam J, Borg A, et al.: Survival of BRCA1 breast and ovarian cancer patients: a population-based study from southern Sweden. J Clin Oncol 16 (2): 397-404, 1998.
199. Stoppa-Lyonnet D, Ansquer Y, Dreyfus H, et al.: Familial invasive breast cancers: worse outcome related to BRCA1 mutations. J Clin Oncol 18 (24): 4053-9, 2000.
200. Haffty BG, Harrold E, Khan AJ, et al.: Outcome of conservatively managed early-onset breast cancer by BRCA1/2 status. Lancet 359 (9316): 1471-7, 2002.
201. Robson M, Levin D, Federici M, et al.: Breast conservation therapy for invasive breast cancer in Ashkenazi women with BRCA gene founder mutations. J Natl Cancer Inst 91 (24): 2112-7, 1999.
202. Robson ME, Chappuis PO, Satagopan J, et al.: A combined analysis of outcome following breast cancer: differences in survival based on BRCA1/BRCA2 mutation status and administration of adjuvant treatment. Breast Cancer Res 6 (1): R8-R17, 2004.
203. Rennert G, Bisland-Naggan S, Barnett-Griness O, et al.: Clinical outcomes of breast cancer in carriers of BRCA1 and BRCA2 mutations. N Engl J Med 357 (2): 115-23, 2007.
204. Brekelmans CT, Tilanus-Linthorst MM, Seynaeve C, et al.: Tumour characteristics, survival and prognostic factors of hereditary breast cancer from BRCA2-, BRCA1- and non-BRCA1/2 families as compared to sporadic breast cancer cases. Eur J Cancer 43 (5): 867-76, 2007.
205. Marcus JN, Watson P, Page DL, et al.: BRCA2 hereditary breast cancer pathophenotype. Breast Cancer Res Treat 44 (3): 275-7, 1997.
206. Agnarsson BA, Jonasson JG, Björnsdottir IB, et al.: Inherited BRCA2 mutation associated with high grade breast cancer. Breast Cancer Res Treat 47 (2): 121-7, 1998.
207. Lakhani SR, Jacquemier J, Sloane JP, et al.: Multifactorial analysis of differences between sporadic breast cancers and cancers involving BRCA1 and BRCA2 mutations. J Natl Cancer Inst 90 (15): 1138-45, 1998.
208. Verhoog LC, Berns EM, Brekelmans CT, et al.: Prognostic significance of germline BRCA2 mutations in hereditary breast cancer patients. J Clin Oncol 18 (21 Suppl): 119S-24S, 2000.
209. Budroni M, Cesaraccio R, Coviello V, et al.: Role of BRCA2 mutation status on overall survival among breast cancer patients from Sardinia. BMC Cancer 9: 62, 2009.
210. Lakhani SR, Manek S, Penault-Llorca F, et al.: Pathology of ovarian cancers in BRCA1 and BRCA2 carriers. Clin Cancer Res 10 (7): 2473-81, 2004.
211. Evans DG, Young K, Bulman M, et al.: Probability of BRCA1/2 mutation varies with ovarian histology: results from screening 442 ovarian cancer families. Clin Genet 73 (4): 338-45, 2008.
212. Tonin PN, Maugard CM, Perret C, et al.: A review of histopathological subtypes of ovarian cancer in BRCA-related French Canadian cancer families. Fam Cancer 6 (4): 491-7, 2007.
213. Crum CP, Drapkin R, Kindelberger D, et al.: Lessons from BRCA: the tubal fimbria emerges as an origin for pelvic serous cancer. Clin Med Res 5 (1): 35-44, 2007.
214. Piek JM, Torrenga B, Hermsen B, et al.: Histopathological characteristics of BRCA1- and BRCA2-associated intraperitoneal cancer: a clinic-based study. Fam Cancer 2 (2): 73-8, 2003.
215. Schorge JO, Muto MG, Lee SJ, et al.: BRCA1-related papillary serous carcinoma of the peritoneum has a unique molecular pathogenesis. Cancer Res 60 (5): 1361-4, 2000.
216. Jazaeri AA, Yee CJ, Sotiriou C, et al.: Gene expression profiles of BRCA1-linked, BRCA2-linked, and sporadic ovarian cancers. J Natl Cancer Inst 94 (13): 990-1000, 2002.
217. Piek JM, van Diest PJ, Zweemer RP, et al.: Dysplastic changes in prophylactically removed Fallopian tubes of women predisposed to developing ovarian cancer. J Pathol 195 (4): 451-6, 2001.
218. Carcangiu ML, Radice P, Manoukian S, et al.: Atypical epithelial proliferation in fallopian tubes in prophylactic salpingo-oophorectomy specimens from BRCA1 and BRCA2 germline mutation carriers. Int J Gynecol Pathol 23 (1): 35-40, 2004.
219. Rubin SC, Benjamin I, Behbakht K, et al.: Clinical and pathological features of ovarian cancer in women with germ-line mutations of BRCA1. N Engl J Med 335 (19): 1413-6, 1996.
220. Ben David Y, Chetrit A, Hirsh-Yechezkel G, et al.: Effect of BRCA mutations on the length of survival in epithelial ovarian tumors. J Clin Oncol 20 (2): 463-6, 2002.
221. Cass I, Baldwin RL, Varkey T, et al.: Improved survival in women with BRCA-associated ovarian carcinoma. Cancer 97 (9): 2187-95, 2003.
222. Aida H, Takakuwa K, Nagata H, et al.: Clinical features of ovarian cancer in Japanese women with germ-line mutations of BRCA1. Clin Cancer Res 4 (1): 235-40, 1998.
223. Boyd J, Sonoda Y, Federici MG, et al.: Clinicopathologic features of BRCA-linked and sporadic ovarian cancer. JAMA 283 (17): 2260-5, 2000.
224. Tan DS, Rothermundt C, Thomas K, et al.: "BRCAness" syndrome in ovarian cancer: a case-control study describing the clinical features and outcome of patients with epithelial ovarian cancer associated with BRCA1 and BRCA2 mutations. J Clin Oncol 26 (34): 5530-6, 2008.
225. Chetrit A, Hirsh-Yechezkel G, Ben-David Y, et al.: Effect of BRCA1/2 mutations on long-term survival of patients with invasive ovarian cancer: the national Israeli study of ovarian cancer. J Clin Oncol 26 (1): 20-5, 2008.
226. Pal T, Permuth-Wey J, Kapoor R, et al.: Improved survival in BRCA2 carriers with ovarian cancer. Fam Cancer 6 (1): 113-9, 2007.
227. Zweemer RP, Verheijen RH, Coebergh JW, et al.: Survival analysis in familial ovarian cancer, a case control study. Eur J Obstet Gynecol Reprod Biol 98 (2): 219-23, 2001.
228. Pharoah PD, Easton DF, Stockton DL, et al.: Survival in familial, BRCA1-associated, and BRCA2-associated epithelial ovarian cancer. United Kingdom Coordinating Committee for Cancer Research (UKCCCR) Familial Ovarian Cancer Study Group. Cancer Res 59 (4): 868-71, 1999.
229. Buller RE, Shahin MS, Geisler JP, et al.: Failure of BRCA1 dysfunction to alter ovarian cancer survival. Clin Cancer Res 8 (5): 1196-202, 2002.
230. Garber JE, Goldstein AM, Kantor AF, et al.: Follow-up study of twenty-four families with Li-Fraumeni syndrome. Cancer Res 51 (22): 6094-7, 1991.
231. Bottomley RH, Condit PT: Cancer families. Cancer Bull 20: 22-24, 1968.
232. Malkin D: The Li-Fraumeni syndrome. Cancer: Principles and Practice of Oncology Updates 7(7): 1-14, 1993.
233. Olivier M, Goldgar DE, Sodha N, et al.: Li-Fraumeni and related syndromes: correlation between tumor type, family structure, and TP53 genotype. Cancer Res 63 (20): 6643-50, 2003.
234. Gonzalez KD, Noltner KA, Buzin CH, et al.: Beyond Li Fraumeni Syndrome: clinical characteristics of families with p53 germline mutations. J Clin Oncol 27 (8): 1250-6, 2009.
235. Harris CC, Hollstein M: Clinical implications of the p53 tumor-suppressor gene. N Engl J Med 329 (18): 1318-27, 1993.
236. Sidransky D, Tokino T, Helzlsouer K, et al.: Inherited p53 gene mutations in breast cancer. Cancer Res 52 (10): 2984-6, 1992.
237. Tsou HC, Teng DH, Ping XL, et al.: The role of MMAC1 mutations in early-onset breast cancer: causative in association with Cowden syndrome and excluded in BRCA1-negative cases. Am J Hum Genet 61 (5): 1036-43, 1997.
238. Pilarski R, Eng C: Will the real Cowden syndrome please stand up (again)? Expanding mutational and clinical spectra of the PTEN hamartoma tumour syndrome. J Med Genet 41 (5): 323-6, 2004.
239. Olopade OI, Weber BL: Breast cancer genetics: toward molecular characterization of individuals at increased risk for breast cancer: part I. Cancer: Principles and Practice of Oncology Updates 12(10): 1-12, 1998.
240. Nelen MR, Padberg GW, Peeters EA, et al.: Localization of the gene for Cowden disease to chromosome 10q22-23. Nat Genet 13 (1): 114-6, 1996.
241. Lachlan KL, Lucassen AM, Bunyan D, et al.: Cowden syndrome and Bannayan Riley Ruvalcaba syndrome represent one condition with variable expression and age-related penetrance: results of a clinical study of PTEN mutation carriers. J Med Genet 44 (9): 579-85, 2007.
242. Lynch ED, Ostermeyer EA, Lee MK, et al.: Inherited mutations in PTEN that are associated with breast cancer, cowden disease, and juvenile polyposis. Am J Hum Genet 61 (6): 1254-60, 1997.
243. Myers MP, Tonks NK: PTEN: sometimes taking it off can be better than putting it on. Am J Hum Genet 61 (6): 1234-8, 1997.
244. Peutz JL: On a very remarkable case of familial polyposis of the mucous membrane of the intestinal tract and nasopharynx accompanied by peculiar pigmentations of the skin and mucous membrane. Ned Tijdschr Geneeskd 10: 134-146, 1921.
245. Jeghers H, McKusick VA, Katz KH: Generalized intestinal polyposis and melanin spots of the oral mucosa, lips and digits: a syndrome of diagnostic significance. N Engl J Med 241(25): 993-1005, 1949.
246. Spigelman AD, Murday V, Phillips RK: Cancer and the Peutz-Jeghers syndrome. Gut 30 (11): 1588-90, 1989.
247. Gruber SB, Entius MM, Petersen GM, et al.: Pathogenesis of adenocarcinoma in Peutz-Jeghers syndrome. Cancer Res 58 (23): 5267-70, 1998.
248. Hemminki A, Markie D, Tomlinson I, et al.: A serine/threonine kinase gene defective in Peutz-Jeghers syndrome. Nature 391 (6663): 184-7, 1998.
249. Jenne DE, Reimann H, Nezu J, et al.: Peutz-Jeghers syndrome is caused by mutations in a novel serine threonine kinase. Nat Genet 18 (1): 38-43, 1998.
250. Ylikorkala A, Avizienyte E, Tomlinson IP, et al.: Mutations and impaired function of LKB1 in familial and non-familial Peutz-Jeghers syndrome and a sporadic testicular cancer. Hum Mol Genet 8 (1): 45-51, 1999.
251. Yoon KA, Ku JL, Choi HS, et al.: Germline mutations of the STK11 gene in Korean Peutz-Jeghers syndrome patients. Br J Cancer 82 (8): 1403-6, 2000.
252. Westerman AM, Entius MM, Boor PP, et al.: Novel mutations in the LKB1/STK11 gene in Dutch Peutz-Jeghers families. Hum Mutat 13 (6): 476-81, 1999.
253. Lim W, Hearle N, Shah B, et al.: Further observations on LKB1/STK11 status and cancer risk in Peutz-Jeghers syndrome. Br J Cancer 89 (2): 308-13, 2003.
254. Hearle N, Schumacher V, Menko FH, et al.: Frequency and spectrum of cancers in the Peutz-Jeghers syndrome. Clin Cancer Res 12 (10): 3209-15, 2006.
255. Giardiello FM, Brensinger JD, Tersmette AC, et al.: Very high risk of cancer in familial Peutz-Jeghers syndrome. Gastroenterology 119 (6): 1447-53, 2000.
256. Humphries AL Jr, Shepherd MH, Peters HJ: Peutz-Jeghers syndrome with colonic adenocarcinoma and ovarian tumor. JAMA 197(4): 138-140, 1966.
257. Christian CD, McLoughlin TG, Cathcart ER, et al.: Peutz-Jeghers syndrome associated with functioning ovarian tumor. JAMA 190(10):157-160, 1964.
258. Solh HM, Azoury RS, Najjar SS: Peutz-Jeghers syndrome associated with precocious puberty. J Pediatr 103 (4): 593-5, 1983.
259. Scully RE: Sex cord tumor with annular tubules a distinctive ovarian tumor of the Peutz-Jeghers syndrome. Cancer 25 (5): 1107-21, 1970.

Low-Penetrance Predisposition to Breast and Ovarian Cancer

Background

Mutations in BRCA1, BRCA2, and the genes involved in other rare syndromes discussed above account for less than 25% of the excess familial risk of breast cancer.[1] Despite intensive genetic linkage studies, there do not appear to be other BRCA1/BRCA2-like high-penetrance genes that account for a significant fraction of the remaining multiple-case familial clusters.[2] These observations suggest that the remaining breast cancer susceptibility is polygenic in nature, meaning that a relatively large number of low-penetrance genes are involved.[3] Each locus would be expected to have a relatively small effect on breast cancer risk and would not produce dramatic familial aggregation or influence patient management. However in combination with other genetic loci and/or environmental factors, particularly given how common these can be, variants of this kind might significantly alter breast cancer risk. These types of genetic variations are sometimes referred to as "polymorphisms", meaning that the gene or locus occurs in several "forms" within the population (and more formally defined as polymorphic when at least 1% of chromosomes at a position vary from each other). Most loci that are polymorphic have no influence on disease risk or human traits (benign polymorphisms), while those that are associated with a difference in risk of disease or a human trait (however subtle) are sometimes termed "disease-associated polymorphisms" or "functionally relevant polymorphisms." This polygenic model of susceptibility is consistent with the observed patterns of familial aggregation of breast cancer.[4] Although the clinical significance and causality of associations with breast cancer are often difficult to evaluate and establish, genetic polymorphisms may account for why some women are more sensitive than others to environmental carcinogens.[5]

Polymorphisms underlying polygenic susceptibility to breast cancer are considered low penetrance, a term often applied to sequence variants associated with a minimal to moderate risk. This is in contrast to "high-penetrance" variants or alleles that are typically associated with more severe phenotypes, for example those BRCA1/BRCA2 mutations leading to an autosomal dominant inheritance patterns in a family. The definition of a "moderate" risk of cancer is arbitrary, but it is usually considered to be in the range of a relative risk of 1.5–2.0. Because these types of sequence variants (also called low-penetrance genes, alleles, mutations, and polymorphisms) are relatively common in the population, their contribution to total cancer risk is estimated to be much higher than the attributable risk in the population from mutations in BRCA1 and BRCA2. For example, it is estimated by segregation analysis that half of all breast cancer occurs in 12% of the population that is deemed most susceptible.[3] There are no known low-penetrance variants in BRCA1/BRCA2. The N372H variation in BRCA2, initially thought to be a low-penetrance allele, was not verified in a large combined analysis.[6]

Two strategies have been taken to identify low-penetrance polymorphisms leading to breast cancer susceptibility: candidate gene and genome-wide searches. Both involve the epidemiologic case-control study design. The candidate gene approach involves selecting genes based on their known or presumed biological function, relevance to carcinogenesis or organ physiology, and searching for or testing known genetic variants for an association with cancer risk. This strategy relies on imperfect and incomplete biological knowledge, and has been relatively disappointing [6,7] despite some confirmed associations, as described below. It has largely been replaced by the genome-wide association studies (GWAS) in which a very large number of single nucleotide polymorphisms (SNPs) (potentially 1,000,000 or more) are chosen within the genome and tested largely without regard to their possible biological function, but instead to capture more uniformly all genetic variation throughout the genome.

Breast Cancer Susceptibility Genes Identified Through Candidate Gene Approaches

CHEK2

CHEK2 (OMIM), a gene involved in the DNA damage repair response pathway, was initially evaluated as a potential cause of Li-Fraumeni syndrome (LFS).[8] It does not appear to be a common cause of LFS.[9] However, based on numerous studies, a polymorphism, 1100delC, appears to be a rare, low-penetrance cancer susceptibility allele.[10,11,12,13,14,15] The deletion was present in 1.2% of the European controls, 4.2% of the European BRCA1/2-negative familial breast cancer cases, and 1.4% of unselected female breast cancer cases.[10] In a group of 1,479 Dutch women younger than 50 years with invasive breast cancer, 3.7% were found to have the CHEK2 1100delC mutation.[16] In both Europe and the United States (where the mutation appears to be slightly less common), additional studies, including a large prospective study,[17] have detected the mutation in 4% to 11% of familial cases of breast cancer and overall have found an approximately 1.5-fold to 3-fold increased risk of female breast cancer.[18,19,20,21] A multicenter combined analysis and reanalysis of nearly 20,000 subjects from ten case-control studies, however, has verified a significant 2.3-fold excess of breast cancer among mutation carriers.[22] Two studies suggest that the risk associated with a CHEK2 1100delC mutation was stronger in the families of probands ascertained because of bilateral breast cancer.[23,24] At least one study has also suggested that the mutation may be associated with both breast and colorectal cancer.[19] Although the initial report [15] and at least one other [25] suggested that male mutation carriers were at a significantly increased risk of breast cancer, several other studies have failed to confirm the association.[26,27,28,29]

The contribution of CHEK2 mutations to breast cancer may depend on the population studied, with a potentially higher mutation prevalence in Poland.[30] CHEK2 mutation carriers in Poland may be more susceptible to ER-positive breast cancer.[31] Although a meta-analysis of 1100delC mutation carriers estimated the risk of breast cancer to be 42% by age 70 years in women with a family history of breast cancer,[32] the clinical applicability of this finding remains uncertain due to low mutation prevalence and lack of guidelines for clinical management.[33]

ATM

Ataxia telangiectasia (AT) (OMIM) is an autosomal recessive disorder characterized by neurologic deterioration, telangiectasias, immunodeficiency states, and hypersensitivity to ionizing radiation. It is estimated that 1% of the general population may be heterozygote carriers of ATM mutations(OMIM).[34] More than 300 mutations in the gene have been identified to date, most of which are truncating mutations.[35] ATM proteins have been shown to play a role in cell cycle control.[36,37,38] In vitro, AT cells are sensitive to ionizing radiation and radiomimetic drugs, and lack cell cycle regulatory properties after exposure to radiation.[39]

Initial studies searching for an excess of ATM mutations among breast cancer patients provided conflicting results, perhaps due to study design and mutation testing strategies.[40,41,42,43,44,45,46,47,48,49,50] However, two large epidemiologic studies have demonstrated a statistically increased risk of breast cancer among female heterozygote carriers, with an estimated relative risk of approximately 2.0.[50,51] Despite this convincing epidemiologic association, the clinical application of testing for ATM mutations is unclear due to the wide mutational spectrum and the logistics of testing. Because the presence of a mutation could pose a risk in screening-related radiation exposure, further work is needed.

BRIP1

BRIP1 (also known as BACH1) encodes a helicase that interacts with the BRCT domain of BRCA1. This gene also has a role in BRCA1-dependent DNA repair and cell cycle checkpoint function. Biallellic mutations in BRIP1 are a cause of Fanconi anemia,[52,53,54] much like such mutations in BRCA2. Inactivating mutations of BRIP1 are associated with an increased risk of breast cancer. Over 3,000 individuals from BRCA1/BRCA2 mutation negative families were examined for BRIP1 mutations. Mutations were identified in 9 of 1,212 individuals with breast cancer but in only 2 of 2,081 controls (P = 0.003). The relative risk of breast cancer was estimated to be 2.0 (95% confidence interval (CI), 1.2–3.2, P = 0.012). Of note, in families with BRIP1 mutations and multiple cases of breast cancer, there was incomplete segregation of the mutation with breast cancer, consistent with a low penetrance allele and similar to that seen with CHEK2.[55]

PALB2

PALB2 (partner and localizer of BRCA2) interacts with the BRCA2 protein and plays a role in homologous recombination and double stranded DNA repair. Similar to BRIP1 and BRCA2, biallelic mutations in PALB2 have also been shown to cause Fanconi anemia.[56] PALB2 mutations were found in 10 of 923 (1.1%) individuals with BRCA1 and BRCA2 mutation negative familial breast cancer, compared to none of 1084 (0%) controls (P = .0004). One of the ten families with a PALB2 mutation included a case of male breast cancer, raising the possibility that male breast cancer is included in the spectrum of PALB2. Similar to BRIP1 and CHEK2, there was incomplete segregation of PALB2 mutations in families with hereditary breast cancer.[57] A Finnish PALB2 founder mutation (c.1592delT) has been reported to confer a 40% risk of breast cancer to age 70 years,[58] and is associated with a high incidence (54%) of triple-negative disease and lower survival.[59]

CASP8 and TGFB1

The Breast Cancer Association Consortium (BCAC) investigated single nucleotide polymorphisms identified in previous studies as possibly associated with excess breast cancer risk in 15,000 to 20,000 cases and 15,000 to 20,000 controls. Two SNPs, CASP80 D302H and TGFB1 L10P, were associated with invasive breast cancer with relative risks of 0.88 (95% CI, 0.84–0.92) and 1.08 (95% CI, 1.04–1.11) respectively.[60]

Genome-Wide Searches

In contrast to assessing candidate genes and/or alleles, genome wide association studies involve comparing a very large set of genetic variants spread throughout the genome. The current paradigm uses sets of 100,000 to 1,000,000 SNPs that are chosen to capture a large portion of common variation within the genome based on the HapMap project.[61,62] By comparing allele frequencies between a large number of cases and controls, typically 1,000 or more of each, and validating promising signals in replication sets of subjects, very robust statistical signals of association have been obtained.[63,64,65] The strong correlation between many SNPs that are physically close to each other on the chromosome (linkage disequilibrium) allows one to "scan" the genome for susceptibility alleles even if the biologically relevant variant is not within the tested set of SNPs. While this between-SNP correlation allows one to interrogate the majority of the genome without having to assay every SNP, when a validated association is obtained, it is not usually obvious which of the many correlated variants is the causal one.

Genome-wide searches are showing great promise in identifying common, low-penetrance susceptibility alleles for many complex diseases [66] including breast cancer.[67,68,69] The first study involved an initial scan in familial breast cancer cases followed by replication in two large sample sets of sporadic breast cancer, the final being a collection of over 20,000 cases and 20,000 controls from the BCAC, an international group of investigators.[67] Five distinct genomic regions were identified that were within or near the FGFR2, TNRC9, MAP3K1, and LSP1 genes or at the chromosome 8q region. Subsequent genome-wide studies have replicated these loci and identified additional ones, as summarized in the following table.[68,69,70,70,71,72,73,74,75] An online catalog of SNP-trait associations from published genome-wide association studies for use in investigating genomic characteristics of trait/disease-associated SNPs (TASs) is available.

Table 6. High-probability breast cancer susceptibility loci for sporadic breast cancer identified through genome-wide association studies

* Initial study that provided convincing evidence for each locus.
Putative Gene(s) Chromosome SNP(s) Study Citations*
FGFR2 10q26.13 rs2981582 [67]
TOX3 16q12.1 rs3803662 [67]
MAP3K1 5q11.2 rs889312 [67]
Intergenic 8q24.21 rs13281615 [67]
LSP1 11p15.5 rs3817198 [67]
Intergenic 2q35 rs13387042 [68]
ESR1 6q25.1 rs2046210 [71]
MRPS30 5p12 rs10941679 [74]
Intergenic 1p11.2 rs11249433 [76]
RAD51B 14q24.1 rs999737 [76]
SLC4A7,NEK10 3p24 rs4973786 [75]
COX11 17q23.2 rs6504950 [75]

Although the statistical evidence for an association between genetic variation at these loci and breast cancer risk is overwhelming, the biologically relevant variants and the mechanism by which they lead to increased risk are unknown and will require further genetic and functional characterization. Additionally, these loci are associated with very modest risk (typically odds ratio < 1.5), with more risk variants likely to be identified. At this time, because their individual and collective influences on cancer risk have not been evaluated prospectively, they are not considered clinically relevant. Furthermore, recent reports have suggested that common moderate-risk SNPs have limited potential to improve models for individualized risk assessment.[77,78] However, they may be of potential utility in risk stratification to improve the efficiency of population screening programs.[77]

References:

1. Easton DF: How many more breast cancer predisposition genes are there? Breast Cancer Res 1 (1): 14-7, 1999.
2. Smith P, McGuffog L, Easton DF, et al.: A genome wide linkage search for breast cancer susceptibility genes. Genes Chromosomes Cancer 45 (7): 646-55, 2006.
3. Pharoah PD, Antoniou A, Bobrow M, et al.: Polygenic susceptibility to breast cancer and implications for prevention. Nat Genet 31 (1): 33-6, 2002.
4. Antoniou AC, Pharoah PP, Smith P, et al.: The BOADICEA model of genetic susceptibility to breast and ovarian cancer. Br J Cancer 91 (8): 1580-90, 2004.
5. Chen YC, Hunter DJ: Molecular epidemiology of cancer. CA Cancer J Clin 55 (1): 45-54; quiz 57, 2005 Jan-Feb.
6. Breast Cancer Association Consortium: Commonly studied single-nucleotide polymorphisms and breast cancer: results from the Breast Cancer Association Consortium. J Natl Cancer Inst 98 (19): 1382-96, 2006.
7. Dunning AM, Healey CS, Pharoah PD, et al.: A systematic review of genetic polymorphisms and breast cancer risk. Cancer Epidemiol Biomarkers Prev 8 (10): 843-54, 1999.
8. Bell DW, Varley JM, Szydlo TE, et al.: Heterozygous germ line hCHK2 mutations in Li-Fraumeni syndrome. Science 286 (5449): 2528-31, 1999.
9. Sodha N, Houlston RS, Bullock S, et al.: Increasing evidence that germline mutations in CHEK2 do not cause Li-Fraumeni syndrome. Hum Mutat 20 (6): 460-2, 2002.
10. Meijers-Heijboer H, van den Ouweland A, Klijn J, et al.: Low-penetrance susceptibility to breast cancer due to CHEK2(*)1100delC in noncarriers of BRCA1 or BRCA2 mutations. Nat Genet 31 (1): 55-9, 2002.
11. Kuschel B, Auranen A, Gregory CS, et al.: Common polymorphisms in checkpoint kinase 2 are not associated with breast cancer risk. Cancer Epidemiol Biomarkers Prev 12 (8): 809-12, 2003.
12. Sodha N, Bullock S, Taylor R, et al.: CHEK2 variants in susceptibility to breast cancer and evidence of retention of the wild type allele in tumours. Br J Cancer 87 (12): 1445-8, 2002.
13. Ingvarsson S, Sigbjornsdottir BI, Huiping C, et al.: Mutation analysis of the CHK2 gene in breast carcinoma and other cancers. Breast Cancer Res 4 (3): R4, 2002.
14. Vahteristo P, Bartkova J, Eerola H, et al.: A CHEK2 genetic variant contributing to a substantial fraction of familial breast cancer. Am J Hum Genet 71 (2): 432-8, 2002.
15. Meijers-Heijboer H, Wijnen J, Vasen H, et al.: The CHEK2 1100delC mutation identifies families with a hereditary breast and colorectal cancer phenotype. Am J Hum Genet 72 (5): 1308-14, 2003.
16. Schmidt MK, Tollenaar RA, de Kemp SR, et al.: Breast cancer survival and tumor characteristics in premenopausal women carrying the CHEK2*1100delC germline mutation. J Clin Oncol 25 (1): 64-9, 2007.
17. Weischer M, Bojesen SE, Tybjaerg-Hansen A, et al.: Increased risk of breast cancer associated with CHEK2*1100delC. J Clin Oncol 25 (1): 57-63, 2007.
18. Offit K, Pierce H, Kirchhoff T, et al.: Frequency of CHEK2*1100delC in New York breast cancer cases and controls. BMC Med Genet 4 (1): 1, 2003.
19. Oldenburg RA, Kroeze-Jansema K, Kraan J, et al.: The CHEK2*1100delC variant acts as a breast cancer risk modifier in non-BRCA1/BRCA2 multiple-case families. Cancer Res 63 (23): 8153-7, 2003.
20. Neuhausen S, Dunning A, Steele L, et al.: Role of CHEK2*1100delC in unselected series of non-BRCA1/2 male breast cancers. Int J Cancer 108 (3): 477-8, 2004.
21. Ohayon T, Gal I, Baruch RG, et al.: CHEK2*1100delC and male breast cancer risk in Israel. Int J Cancer 108 (3): 479-80, 2004.
22. CHEK2 Breast Cancer Case-Control Consortium.: CHEK2*1100delC and susceptibility to breast cancer: a collaborative analysis involving 10,860 breast cancer cases and 9,065 controls from 10 studies. Am J Hum Genet 74 (6): 1175-82, 2004.
23. Johnson N, Fletcher O, Naceur-Lombardelli C, et al.: Interaction between CHEK2*1100delC and other low-penetrance breast-cancer susceptibility genes: a familial study. Lancet 366 (9496): 1554-7, 2005 Oct 29-Nov 4.
24. Fletcher O, Johnson N, Dos Santos Silva I, et al.: Family history, genetic testing, and clinical risk prediction: pooled analysis of CHEK2 1100delC in 1,828 bilateral breast cancers and 7,030 controls. Cancer Epidemiol Biomarkers Prev 18 (1): 230-4, 2009.
25. Wasielewski M, den Bakker MA, van den Ouweland A, et al.: CHEK2 1100delC and male breast cancer in the Netherlands. Breast Cancer Res Treat 116 (2): 397-400, 2009.
26. Osorio A, Rodríguez-López R, Díez O, et al.: The breast cancer low-penetrance allele 1100delC in the CHEK2 gene is not present in Spanish familial breast cancer population. Int J Cancer 108 (1): 54-6, 2004.
27. Syrjäkoski K, Kuukasjärvi T, Auvinen A, et al.: CHEK2 1100delC is not a risk factor for male breast cancer population. Int J Cancer 108 (3): 475-6, 2004.
28. Tsou HC, Teng DH, Ping XL, et al.: The role of MMAC1 mutations in early-onset breast cancer: causative in association with Cowden syndrome and excluded in BRCA1-negative cases. Am J Hum Genet 61 (5): 1036-43, 1997.
29. Olopade OI, Weber BL: Breast cancer genetics: toward molecular characterization of individuals at increased risk for breast cancer: part I. Cancer: Principles and Practice of Oncology Updates 12(10): 1-12, 1998.
30. Cybulski C, Górski B, Huzarski T, et al.: CHEK2-positive breast cancers in young Polish women. Clin Cancer Res 12 (16): 4832-5, 2006.
31. Cybulski C, Huzarski T, Byrski T, et al.: Estrogen receptor status in CHEK2-positive breast cancers: implications for chemoprevention. Clin Genet 75 (1): 72-8, 2009.
32. Weischer M, Bojesen SE, Ellervik C, et al.: CHEK2*1100delC genotyping for clinical assessment of breast cancer risk: meta-analyses of 26,000 patient cases and 27,000 controls. J Clin Oncol 26 (4): 542-8, 2008.
33. Offit K, Garber JE: Time to check CHEK2 in families with breast cancer? J Clin Oncol 26 (4): 519-20, 2008.
34. Savitsky K, Bar-Shira A, Gilad S, et al.: A single ataxia telangiectasia gene with a product similar to PI-3 kinase. Science 268 (5218): 1749-53, 1995.
35. Telatar M, Teraoka S, Wang Z, et al.: Ataxia-telangiectasia: identification and detection of founder-effect mutations in the ATM gene in ethnic populations. Am J Hum Genet 62 (1): 86-97, 1998.
36. Uhrhammer N, Bay JO, Bignon YJ: Seventh International Workshop on Ataxia-Telangiectasia. Cancer Res 58 (15): 3480-5, 1998.
37. Ahmed M, Rahman N: ATM and breast cancer susceptibility. Oncogene 25 (43): 5906-11, 2006.
38. Khanna KK, Chenevix-Trench G: ATM and genome maintenance: defining its role in breast cancer susceptibility. J Mammary Gland Biol Neoplasia 9 (3): 247-62, 2004.
39. Gilad S, Chessa L, Khosravi R, et al.: Genotype-phenotype relationships in ataxia-telangiectasia and variants. Am J Hum Genet 62 (3): 551-61, 1998.
40. FitzGerald MG, Bean JM, Hegde SR, et al.: Heterozygous ATM mutations do not contribute to early onset of breast cancer. Nat Genet 15 (3): 307-10, 1997.
41. Chen J, Birkholtz GG, Lindblom P, et al.: The role of ataxia-telangiectasia heterozygotes in familial breast cancer. Cancer Res 58 (7): 1376-9, 1998.
42. Bay JO, Grancho M, Pernin D, et al.: No evidence for constitutional ATM mutation in breast/gastric cancer families. Int J Oncol 12 (6): 1385-90, 1998.
43. Laake K, Vu P, Andersen TI, et al.: Screening breast cancer patients for Norwegian ATM mutations. Br J Cancer 83 (12): 1650-3, 2000.
44. Dörk T, Bendix R, Bremer M, et al.: Spectrum of ATM gene mutations in a hospital-based series of unselected breast cancer patients. Cancer Res 61 (20): 7608-15, 2001.
45. Teraoka SN, Malone KE, Doody DR, et al.: Increased frequency of ATM mutations in breast carcinoma patients with early onset disease and positive family history. Cancer 92 (3): 479-87, 2001.
46. Chenevix-Trench G, Spurdle AB, Gatei M, et al.: Dominant negative ATM mutations in breast cancer families. J Natl Cancer Inst 94 (3): 205-15, 2002.
47. Thorstenson YR, Roxas A, Kroiss R, et al.: Contributions of ATM mutations to familial breast and ovarian cancer. Cancer Res 63 (12): 3325-33, 2003.
48. Cavaciuti E, Laugé A, Janin N, et al.: Cancer risk according to type and location of ATM mutation in ataxia-telangiectasia families. Genes Chromosomes Cancer 42 (1): 1-9, 2005.
49. Olsen JH, Hahnemann JM, Børresen-Dale AL, et al.: Breast and other cancers in 1445 blood relatives of 75 Nordic patients with ataxia telangiectasia. Br J Cancer 93 (2): 260-5, 2005.
50. Renwick A, Thompson D, Seal S, et al.: ATM mutations that cause ataxia-telangiectasia are breast cancer susceptibility alleles. Nat Genet 38 (8): 873-5, 2006.
51. Thompson D, Duedal S, Kirner J, et al.: Cancer risks and mortality in heterozygous ATM mutation carriers. J Natl Cancer Inst 97 (11): 813-22, 2005.
52. Levitus M, Waisfisz Q, Godthelp BC, et al.: The DNA helicase BRIP1 is defective in Fanconi anemia complementation group J. Nat Genet 37 (9): 934-5, 2005.
53. Levran O, Attwooll C, Henry RT, et al.: The BRCA1-interacting helicase BRIP1 is deficient in Fanconi anemia. Nat Genet 37 (9): 931-3, 2005.
54. Litman R, Peng M, Jin Z, et al.: BACH1 is critical for homologous recombination and appears to be the Fanconi anemia gene product FANCJ. Cancer Cell 8 (3): 255-65, 2005.
55. Seal S, Thompson D, Renwick A, et al.: Truncating mutations in the Fanconi anemia J gene BRIP1 are low-penetrance breast cancer susceptibility alleles. Nat Genet 38 (11): 1239-41, 2006.
56. Reid S, Schindler D, Hanenberg H, et al.: Biallelic mutations in PALB2 cause Fanconi anemia subtype FA-N and predispose to childhood cancer. Nat Genet 39 (2): 162-4, 2007.
57. Rahman N, Seal S, Thompson D, et al.: PALB2, which encodes a BRCA2-interacting protein, is a breast cancer susceptibility gene. Nat Genet 39 (2): 165-7, 2007.
58. Erkko H, Dowty JG, Nikkilä J, et al.: Penetrance analysis of the PALB2 c.1592delT founder mutation. Clin Cancer Res 14 (14): 4667-71, 2008.
59. Heikkinen T, Kärkkäinen H, Aaltonen K, et al.: The breast cancer susceptibility mutation PALB2 1592delT is associated with an aggressive tumor phenotype. Clin Cancer Res 15 (9): 3214-22, 2009.
60. Cox Angela, Dunning Alison, Garcia-Closas Montserrat, et al.: Nature genetics. Nat Genet 39 (5): 352-8, 2007.
61. The International HapMap Consortium.: The International HapMap Project. Nature 426 (6968): 789-96, 2003.
62. Thorisson GA, Smith AV, Krishnan L, et al.: The International HapMap Project Web site. Genome Res 15 (11): 1592-3, 2005.
63. Evans DM, Cardon LR: Genome-wide association: a promising start to a long race. Trends Genet 22 (7): 350-4, 2006.
64. Cardon LR: Genetics. Delivering new disease genes. Science 314 (5804): 1403-5, 2006.
65. Chanock SJ, Manolio T, Boehnke M, et al.: Replicating genotype-phenotype associations. Nature 447 (7145): 655-60, 2007.
66. Wellcome Trust Case Control Consortium.: Genome-wide association study of 14,000 cases of seven common diseases and 3,000 shared controls. Nature 447 (7145): 661-78, 2007.
67. Easton DF, Pooley KA, Dunning AM, et al.: Genome-wide association study identifies novel breast cancer susceptibility loci. Nature 447 (7148): 1087-93, 2007.
68. Stacey SN, Manolescu A, Sulem P, et al.: Common variants on chromosomes 2q35 and 16q12 confer susceptibility to estrogen receptor-positive breast cancer. Nat Genet 39 (7): 865-9, 2007.
69. Hunter DJ, Kraft P, Jacobs KB, et al.: A genome-wide association study identifies alleles in FGFR2 associated with risk of sporadic postmenopausal breast cancer. Nat Genet 39 (7): 870-4, 2007.
70. Gold B, Kirchhoff T, Stefanov S, et al.: Genome-wide association study provides evidence for a breast cancer risk locus at 6q22.33. Proc Natl Acad Sci U S A 105 (11): 4340-5, 2008.
71. Zheng W, Long J, Gao YT, et al.: Genome-wide association study identifies a new breast cancer susceptibility locus at 6q25.1. Nat Genet 41 (3): 324-8, 2009.
72. Kibriya MG, Jasmine F, Argos M, et al.: A pilot genome-wide association study of early-onset breast cancer. Breast Cancer Res Treat 114 (3): 463-77, 2009.
73. Murabito JM, Rosenberg CL, Finger D, et al.: A genome-wide association study of breast and prostate cancer in the NHLBI's Framingham Heart Study. BMC Med Genet 8 (Suppl 1): S6, 2007.
74. Stacey SN, Manolescu A, Sulem P, et al.: Common variants on chromosome 5p12 confer susceptibility to estrogen receptor-positive breast cancer. Nat Genet 40 (6): 703-6, 2008.
75. Ahmed S, Thomas G, Ghoussaini M, et al.: Newly discovered breast cancer susceptibility loci on 3p24 and 17q23.2. Nat Genet 41 (5): 585-90, 2009.
76. Thomas G, Jacobs KB, Kraft P, et al.: A multistage genome-wide association study in breast cancer identifies two new risk alleles at 1p11.2 and 14q24.1 (RAD51L1). Nat Genet 41 (5): 579-84, 2009.
77. Pharoah PD, Antoniou AC, Easton DF, et al.: Polygenes, risk prediction, and targeted prevention of breast cancer. N Engl J Med 358 (26): 2796-803, 2008.
78. Gail MH: Discriminatory accuracy from single-nucleotide polymorphisms in models to predict breast cancer risk. J Natl Cancer Inst 100 (14): 1037-41, 2008.

Interventions

Few data exist on the outcomes of interventions to reduce risk in people with a genetic susceptibility to breast or ovarian cancer. As a result, recommendations for management are primarily based on expert opinion.[1,2,3,4,5] In addition, as outlined in other sections of this summary, uncertainty is often considerable regarding the level of cancer risk associated with a positive family history or genetic test. In this setting, personal preferences are likely to be an important factor in patients' decisions about risk reduction strategies.

Breast Cancer

Screening

Refer to the PDQ summary on Breast Cancer Screening for information on screening in the general population, and to the PDQ summary Cancer Genetics Overview for information on levels of evidence related to screening and prevention.

Breast Self-Examination

In the general population, evidence for the value of breast self-examination (BSE) is limited. Preliminary results have been reported from a randomized study of BSE being conducted in Shanghai, China.[6] At 5 years, no reduction in breast cancer mortality was seen in the BSE group compared with the control group of women, nor was a substantive stage shift seen in breast cancers that were diagnosed. (Refer to the PDQ summary on Breast Cancer Screening for more information.)

Little direct prospective evidence exists regarding BSE among female carriers of a BRCA1 or BRCA2 high-risk mutation, male carriers of a BRCA2 mutation, or women at inherited risk of breast cancer. In the Canadian National Breast Screening Study, women with first-degree relatives with breast cancer had statistically significantly higher BSE competency scores than those without a family history. In a study of 251 high-risk women at a referral center, five breast cancers were detected by self-examination less than a year after a previous screen (as compared with one cancer detected by clinician exam and 11 cancers detected as a result of mammography). Women in the cohort were instructed in self-examination, but it is not stated whether the interval cancers were detected as a result of planned self-examination or incidental discovery of breast masses.[7] In another series of BRCA1/2 mutation carriers, four of nine incident cancers were diagnosed as palpable masses after a reportedly normal mammogram, further suggesting the potential value of self-examination.[8] A task force convened by the Cancer Genetics Studies Consortium has recommended "monthly self-examination beginning early in adult life (e.g., by age 18-21) to establish a regular habit and allow familiarity with the normal characteristics of breast tissue. Education and instruction in self-examination are recommended."[9]

Level of evidence: 5

Clinical Breast Examination

Few prospective data exist regarding clinical breast examination (CBE) among female carriers of a BRCA1 or BRCA2 high-risk mutation, male carriers of a BRCA2 mutation, or women at inherited risk of breast cancer.

The Cancer Genetics Studies Consortium task force concluded, "as with self-examination, the contribution of clinical examination may be particularly important for women at inherited risk of early breast cancer." They recommended that female carriers of a BRCA1 or BRCA2 high-risk mutation undergo annual or semiannual clinical examinations beginning at age 25 to 35 years.[9]

Level of evidence: 5

Mammography

In the general population, strong evidence suggests that regular mammography screening of women aged 50 to 59 years leads to a 25% to 30% reduction in breast cancer mortality. (Refer to the PDQ summary on Breast Cancer Screening for more information.) For women who begin mammographic screening at age 40 to 49 years, a 17% reduction in breast cancer mortality is seen, which occurs 15 years after the start of screening.[10] Observational data from a cohort study of more than 28,000 women suggest that the sensitivity of mammography is lower for young women. In this study, the sensitivity was lowest for younger women (aged 30-49 years) who had a first-degree relative with breast cancer. For these women, mammography detected 69% of breast cancers diagnosed within 13 months of the first screening mammography. By contrast, sensitivity for women younger than 50 years without a family history was 88% (P = .08). For women aged 50 years and older, sensitivity was 93% at 13 months and did not vary by family history.[11] Preliminary data suggest that mammography sensitivity is lower in BRCA1 and BRCA2 carriers than in noncarriers.[8] Subsequent observational studies have found that the positive predictive value (PPV) of mammography increases with age and is highest among older women and among women with a family history of breast cancer.[12] Higher PPVs may be due to increased breast cancer incidence, higher sensitivity, and/or higher specificity.[13] One study found an association between the presence of pushing margins, a histopathologic description of a pattern of invasion, and false-negative mammograms in 28 women, 26 of whom had a BRCA1 mutation and two of whom had a BRCA2 mutation. Pushing margins, characteristic of medullary histology, is associated with an absence of fibrotic reaction.[14] In addition, rapid tumor doubling times may lead to tumors presenting shortly after an apparently normal study. In one study, mean tumor doubling time in BRCA1/2 carriers was 45 days, compared with 84 days in noncarriers.[15] Another study that evaluated mammographic breast density in women with BRCA mutations found no association between mutation status and mammographic density; however, in both carriers and noncarriers, increased breast density was associated with increased breast cancer risk.[16]

The randomized Canadian National Breast Screening Study-2 (NBSS2) compared annual CBE plus mammography to CBE alone in women aged 50 to 59 years from the general population. Both groups were given instruction in BSE.[17] Although mammography detected smaller primary invasive tumors and more invasive as well as ductal carcinomas in situ (DCIS) than CBE, the breast cancer mortality rates in the CBE-plus-mammography group and the CBE- alone group were nearly identical, and compared favorably with other breast cancer screening trials. After a mean follow-up of 13 years (range 11.3–16.0 years), the cumulative breast cancer mortality ratio was 1.02 (95% confidence interval (CI) = 0.78–1.33). One possible explanation of this finding was the careful training and supervision of the health professionals performing CBE.

In a prospective study of 251 individuals with BRCA mutations who received uniform recommendations regarding screening and risk-reducing, or prophylactic, surgery, annual mammography detected breast cancer in six women at a mean of 20.2 months after receipt of BRCA results.[7] The Cancer Genetics Studies Consortium task force has recommended for female carriers of a BRCA1 or BRCA2 high-risk mutation, "annual mammography, beginning at age 25 to 35 years. Mammograms should be done at a consistent location when possible, with prior films available for comparison."[9] Data from prospective studies on the relative benefits and risks of screening with an ionizing radiation tool versus CBE or other nonionizing radiation tools would be useful.[18,19,20]

Certain observations have led to the concern that BRCA mutation carriers may be more prone to radiation-induced breast cancer than women without mutations. The BRCA1 and BRCA2 proteins are known to be important in cellular mechanisms of DNA damage repair, including those involved in repairing radiation-induced damage. Mouse embryos lacking Brca1 or Brca2 are hypersensitive to the effects of ionizing radiation. Some studies have suggested intermediate radiation sensitivity in cells that are heterozygous for a BRCA mutation, but this is not consistent and varies by experimental system and endpoint. A large international case-control study of 1,601 mutation carriers described an increased risk of breast cancer (hazard ratio (HR) = 1.54) among women who were ever exposed to chest x-rays, with risk being highest in women age 40 years and younger, born after 1949, and those exposed to x-rays only before age 20 years.[21] In contrast, two studies of the effect of mammogram exposure on carriers (n = 1,600, n = 162) did not support an association between such exposure and subsequent breast cancer risk.[22,23] In a small study,[23] there was a modest association between lifetime mammogram exposure and risk in BRCA1 mutation carriers (HR = 1.08, P = .03). No significant effect was seen after exclusion of postdiagnosis mammograms. At this time there is insufficient evidence to suggest that mutation carriers should avoid mammography.

Level of evidence: 3

The limited sensitivity of mammography and an interest in methods of screening that do not involve ionizing radiation has led to evaluation of other screening techniques, including magnetic resonance imaging (MRI), breast ultrasound, breast ductal lavage, and digital mammography.

Magnetic Resonance Imaging

Because of the relative insensitivity of mammography in women at hereditary risk for breast cancer, a number of screening modalities have been proposed and investigated in high-risk women, including BRCA mutation carriers. Several studies have described the experience with breast MRI screening in women at risk for breast cancer, including descriptions of relatively large multi-institutional trials.[24,25,26,27,28,29,30] Several considerations must be kept in mind when reviewing these reports:

  • The studies are variable in terms of the underlying population being studied, equipment and signal processing protocols, the manner of reporting results, and the manner in which sensitivity and specificity are calculated.
  • The different screening tests (MRI and mammogram with or without ultrasound) are performed nearly simultaneously in these studies, and the screening modalities are compared to each other. Therefore, sensitivity is defined somewhat differently in these studies than in the American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) of follow-up and outcome reporting.
  • The number of screening rounds is limited, and the distinction between prevalent (first round) and incident cancer detection rates is often unclear.

Despite these caveats, the reported studies consistently demonstrate that breast MRI is more sensitive than either mammography or ultrasound for the detection of hereditary breast cancer. The results of four large studies are presented in Table 7, Summary of MRI Screening Studies in Women at Hereditary Risk for Breast Cancer.[24,25,26,27,28] Most cancers in these programs were screen detected with only 6% of cancers presenting in the interval between screenings. The sensitivity of MRI (as defined by the study methodology) ranged from 71% to 100%. Of the combined studies, 82% of the cancers were identified by MRI compared with 40% by mammography.

Concerns have been raised about the reduced specificity of MRI compared with other screening modalities. In one study, after the initial MRI screen, 16.5% of the patients were recalled for further evaluation, and 7.6% of subjects were recommended to undergo a short-interval follow-up examination at 6 months.[28] These rates declined significantly during later screening rounds, with fewer than 10% of the subjects recalled for more detailed MRI and fewer than 3% recommended to have short interval follow-up. In a second study, Magnetic Resonance Imaging for Breast Screening (MARIBS), the recall rate for additional evaluation was 10.7% per year.[27] The benign biopsy rates in the first study were 11% at first round, 6.6% at second round, and 4.7% at third round.[28] In the MARIBS study, the aggregate surgical biopsy rate was 9 per 1,000 screening episodes, though this may underestimate the burden because follow-up ultrasounds, core-needle biopsies, and fine-needle aspirations have not been included in the numerator of the MARIBS calculation.[27] The PPV of MRI has been calculated differently in the various series and fluctuates somewhat, depending on whether all abnormal examinations or only the examinations that result in a biopsy are counted in the denominator. Generally, the PPV of a recommendation for tissue sampling (as opposed to further investigation) is in the range of 50% in most series.

These trials appear to establish that MRI is superior to mammography in the detection of hereditary breast cancer, and that women participating in these trials including annual MRI screening were less likely to have a cancer not detected by screening.[31] However, mammography clearly identifies some cancers that are not identified by MRI. Most of these mammographically detected cancers in women with a negative MRI appear to be ductal carcinomas in situ, presumably presenting as microcalcifications without significant ductal enhancement. While MRI does appear to be more sensitive than mammogram, it is unknown whether MRI screening results in a survival benefit or even in downstaging compared to mammography alone. One screening study demonstrated that patients were more likely to be diagnosed with small tumors and node-negative disease than women in two nonrandomized control groups.[25] However, a randomized study of screening with or without MRI using tumor stage or mortality as an endpoint has not been performed. Despite the apparent sensitivity of MRI screening, some women in MRI-based programs will nevertheless develop life-threatening breast cancer. The American Cancer Society and the National Comprehensive Cancer Network (NCCN) have recommended the use of annual MRI screening for women at hereditary risk for breast cancer.[3,32]

Table 7. Summary of MRI Screening Studies in Women at Hereditary Risk for Breast Cancer

a Two additional cancers detected at planned 6-month interval ultrasound screening (not included in ultrasound detection proportion).
b Restricted to studies in which ultrasound was performed.
Series Kriege [25] Warner [28] MARIBS [27] Kuhl [33] Totals
N Patients Overall 1,909 236 649 529 3,323
BRCA1/2 Carriers 354 236 120 43 753
N Screening Episodes 4,169 457 1,881 1,542 8,049
N Cancers Baseline 22 13 20 14 69
Subsequent 23 9 15 29 76
Annual Incidence 9.5/1,000   19/1,000 25/1,000  
Detected at Planned Screening 41 21 33 40a 135 (93%)
N Detected by Each Modality Mammography 18 8 14 14 54 (37%)
MRI 32 17 27 39 115 (79%)
Ultrasoundb   7   17 24 (37%)

Level of evidence: 3

Ultrasound

Several studies have reported instances of breast cancer detected by ultrasound that were missed by mammography, as discussed in one review.[34] In a pilot study of ultrasound as an adjunct to mammography in 149 women with moderately increased risk based on family history, one cancer was detected, based on ultrasound findings. Nine other biopsies of benign lesions were performed. One was based on abnormalities on both mammography and ultrasound, and the remaining eight were based on abnormalities on ultrasound alone.[34] A large study of 2,809 women with dense breast tissue (ACRIN-6666) demonstrated that ultrasound increased the detection rate due to breast cancer screening from 7.6 per 1,000 with mammography alone to 11.8 per 1,000 for combined mammography and ultrasound.[35] However, ultrasound screening increases false-positive rates and appears to have a limited benefit in combination with MRI. In a multicenter study of 171 women (92% of whom were BRCA1/2 mutation carriers) undergoing simultaneous mammography, MRI, and ultrasound, no cancers were detected by ultrasound alone.[29] Uncertainties about ultrasound include the effect of screening on mortality, the rate and outcome of false-positive results, and access to experienced breast ultrasonographers.

Level of evidence: None assigned

Digital Mammography

Digital mammography refers to the use of a digital detector to detect and record x-ray images. This technology improves contrast resolution,[36] and has been proposed as a potential strategy for improving the sensitivity of mammography. A screening study comparing digital with routine mammography in 6,736 examinations of women aged 40 years and older found no difference in cancer detection rates;[37] however, digital mammography resulted in fewer recalls. In another study (ACRIN-6652) comparing digital mammography to plain-film mammography in 42,760 women, the overall diagnostic accuracy of the two techniques was similar.[38] When Receiver Operating Characteristic (ROC) curves were compared, digital mammography was more accurate in women younger than 50 years, in women with radiographically dense breasts, and in premenopausal or perimenopausal women.

Level of evidence: 3

Risk modification

Refer to the PDQ summary on Breast Cancer Prevention for information on prevention in the general population, and to the PDQ summary Cancer Genetics Overview for information on levels of evidence related to screening and prevention.

Reproductive Factors

Pregnancy and Lactation

In the general population, breast cancer risk increases with early menarche and late menopause, and is reduced at early first full-term pregnancy. (Refer to the PDQ summary on Breast Cancer Prevention for more information.) In the Nurses' Health Study, these were risk factors among women who did not have a mother or sister with breast cancer.[39] Among women with a family history of breast cancer, pregnancy at any age appeared to be associated with an increase in risk of breast cancer, persisting to age 70 years.

One study evaluated risk modifiers among 333 female carriers of a BRCA1 high-risk mutation. In women with known mutations of the BRCA1 gene, early age at first live birth and parity of three or more have been associated with a lowered risk of breast cancer. A relative risk (RR) of 0.85 was estimated for each additional birth, up to five or more; however, increasing parity appeared to be associated with an increased risk of ovarian cancer.[40,41] In a case-control study from New Zealand, investigators noted no difference in the impact of parity upon the risk of breast cancer between women with a family history of breast cancer and those without a family history.[42]

Studies of the effect of pregnancy on breast cancer risk have revealed complex results. Although the relationship of parity has been inconsistent, several studies have shown that among parous women, an increased number of full-term births is associated with a decrease in breast cancer risk. The influence of age at first birth may differ between BRCA1 and BRCA2 mutation carriers.[43,44,45] Of note, neither therapeutic nor spontaneous abortions appear to be associated with an increased breast cancer risk.[43,46]

Level of evidence: 4aii

In the general population, breastfeeding has been associated with a slight reduction in breast cancer risk in a few studies, including a large collaborative reanalysis of multiple epidemiologic studies,[47] and at least one study suggests that it may be protective in BRCA1 mutation carriers. In a multicenter breast cancer case-control study of 685 BRCA1 and 280 BRCA2 mutation carriers with breast cancer and 965 mutation carriers without breast cancer drawn from multiple-case families, among BRCA1 mutation carriers, breastfeeding for one year or more was associated with approximately a 45% reduced risk of breast cancer.[48] No such reduced risk was observed among BRCA2 mutation carriers. A second study failed to confirm this association.[43]

Oral Contraceptives

Among the general population, oral contraceptives may produce a slight, short-term increase in breast cancer risk. (Refer to the PDQ summary on Breast Cancer Prevention for more information.) In a meta-analysis of data from 54 studies, family history of breast cancer was not associated with any variation in risk associated with oral contraceptive use.[49] In a study of 50 Jewish women younger than 40 years with breast cancer, those with a BRCA1 or BRCA2 high-risk mutation had a higher likelihood of long-term oral contraceptive use (>48 months) before their first pregnancy.[50] The authors concluded that oral contraceptive use might increase the risk of breast cancer among carriers of a BRCA1 or BRCA2 mutation more than in noncarriers. In a case-control study of more than 1,300 pairs of women, each case was matched to a woman with a mutation in the same gene, born within 2 years of the case, and in the same country, who had not developed cancer. Oral contraceptive use was associated with a statistically significant 20% (CI, 2%–40%) increase in risk of breast cancer among BRCA1 mutation carriers, particularly if use:

  • Began before 1975, a period when estrogen doses were relatively high (38% increase, CI 11%–72%).
  • Began before age 30 years (29% increase, CI, 9%–52%).
  • Lasted for 5 or more years (33% increase, CI, 11%–60%).[51]

There was no increased risk associated with use among BRCA2 mutation carriers. A Swedish population-based study of 245 women with breast cancer diagnosed before age 41 years, 19 of whom were BRCA1/BRCA2 mutation carriers, suggested that oral contraceptive use before age 20 years was associated with increased breast cancer risk in both mutation carriers and noncarriers, though the small number of carriers limits the conclusions for this subgroup.[52]

In contrast, a population-based study of 47 BRCA1 and 36 BRCA2 mutation carriers with breast cancer diagnosed before age 40 years, matched to population controls without mutations, found no increased risk of early-onset breast cancer associated with ever use of low-dose contraceptive pills for BRCA2 mutation carriers (odds ratio (OR) = 1.02) and a significantly reduced risk for BRCA1 mutation carriers (OR = 0.22; 95% CI, 0.10–0.49).[53]

One study examined proliferation of normal breast epithelium among women undergoing reduction mammoplasty.[54] The study found a substantially higher cellular proliferation rate among women who used oral contraceptives before their first full-term pregnancy. In addition, among women currently on oral contraceptives, women with a family history of breast cancer had much higher cellular proliferation rates than those women without a family history. These findings are consistent with increased breast cancer risk among women with a family history of breast cancer who use oral contraceptives.

In considering contraceptive options and preventive actions, the potential impact of oral contraceptive use upon the risk of both breast and ovarian cancer, as well as other health-related effects of oral contraceptives, needs to be considered. With regard to breast cancer risk associated with oral contraceptive use, despite conflicting results based on small numbers of carriers, several studies have found a significantly increased risk. A number of important issues remain unresolved including the potential differences between BRCA1/2 mutation carriers, age and duration of exposure, and formulation.

Level of evidence: 3aii

Hormone Replacement Therapy

Both observational and randomized clinical trial data suggest an increased risk of breast cancer associated with hormone replacement therapy (HRT) in the general population.[55,56,57,58] The Women's Health Initiative (WHI) is a randomized controlled trial of approximately 160,000 postmenopausal women investigating the risks and benefits of strategies that may reduce the incidence of heart disease, breast and colorectal cancer, and fractures, including dietary interventions and two trials of hormone therapy. The estrogen-plus-progestin arm of the study, which randomized more than 16,000 women to receive combined hormone therapy or placebo, was halted early because health risks exceeded benefits.[57,58] One of the adverse outcomes prompting closure was a significant increase in both total (245 vs. 185 cases) and invasive (199 vs. 150) breast cancers (RR =1.24; 95% CI, 1.02–1.50, P <.001) in women randomized to receive estrogen and progestin.[58] Results of a follow-up study suggest that the recent reduction in breast cancer incidence, especially among women aged 50 to 69 years, is predominantly related to decrease in use of combined estrogen plus progestin HRT.[59] HRT-related breast cancers had adverse prognostic characteristics (more advanced stages and larger tumors) compared with cancers occurring in the placebo group, and HRT was also associated with a substantial increase in abnormal mammograms.[58]

Breast cancer risk associated with postmenopausal HRT has been variably reported to be increased [60,61,62] or unaffected by a family history of breast cancer;[40,63,64] risk did not vary by family history in the meta-analysis.[49] The WHI study has not reported analyses stratified on breast cancer family history, and subjects have not been systematically tested for BRCA1/2 mutations.[58] Short-term use of hormones for treatment of menopausal symptoms appears to confer little or no breast cancer risk in the general population.[65]

Hormone replacement therapy in BRCA1/2 mutation carriers

The effect of HRT on breast cancer risk among carriers of a BRCA1 or BRCA2 mutation has been examined in two studies. In a prospective study of 462 BRCA1 or BRCA2 mutation carriers, bilateral risk-reducing salpingo-oophorectomy (RRSO) (n = 155) was significantly associated with breast cancer risk reduction overall (hazard ratio [HR] = 0.40; 95% CI, 0.18–0.92). Using mutation carriers without bilateral RRSO or HRT as the comparison group, HRT use (n = 93) did not significantly alter the reduction in breast cancer risk associated with bilateral RRSO (HR = 0.37; 95% CI, 0.14–0.96).[66] In a matched case-control study of 472 postmenopausal women with BRCA1 mutations, HRT use was associated with an overall reduction in breast cancer risk (OR = 0.58; 95% CI, 0.35–0.96, P = .03). A nonsignificant reduction in risk was observed both in women who had undergone bilateral oophorectomy and in those who had not. Women taking estrogen alone had an OR of 0.51 (95% CI, 0.27–0.98, P = .04), while the association with estrogen and progesterone was not statistically significant (OR = 0.66; 95% CI, 0.34–1.27, P = .21).[67] Especially given the differences in estimated risk associated with HRT between observational studies and the Women's Health Initiative (a randomized clinical trial), these findings should be confirmed in randomized prospective studies,[68] but they suggest that HRT in BRCA1/BRCA2 mutation carriers neither increases breast cancer risk nor negates the protective effect of oophorectomy.

Level of evidence: 3aii

Risk Reduction

Tamoxifen

Tamoxifen (a synthetic antiestrogen) increases breast-cell growth inhibitory factors and concomitantly reduces breast-cell growth stimulatory factors. The National Surgical Adjuvant Breast and Bowel Project Breast Cancer Prevention Trial (NSABP-P1), a prospective randomized double-blind trial, compared tamoxifen (20 mg/day) to placebo for 5 years. Tamoxifen was shown to reduce the risk of invasive breast cancer by 49%. The protective effect was largely confined to estrogen receptor–positive breast cancer, which was reduced by 69%. The incidence of estrogen receptor–negative cancer was not significantly reduced.[69] Similar reductions were noted in the risk of preinvasive breast cancer. Reductions in breast cancer risk were noted among women with a family history of breast cancer and in those without a family history. These benefits were associated with an increased incidence of endometrial cancers and thrombotic events among women older than 50 years. Interim data from two European tamoxifen prevention trials did not show a reduction in breast cancer risk with tamoxifen after a median follow-up of 48 months [70] or 70 months,[71] respectively. In one trial, however, reduction in breast cancer risk was seen among a subgroup who also used HRT.[70] These trials varied considerably in study design and populations. (Refer to the PDQ summary on Breast Cancer Prevention for more information.)

A substudy of the NSABP-P1 trial evaluated the effectiveness of tamoxifen in preventing breast cancer in BRCA1/2 mutation carriers older than 35 years. BRCA2-positive women benefited from tamoxifen to the same extent as BRCA1/2 mutation–negative participants; however, tamoxifen use among healthy women with BRCA1 mutations did not appear to reduce breast cancer incidence. These data must be viewed with caution in view of the small number of mutation carriers in the sample (8 BRCA1 carriers and 11 BRCA2 carriers).[72]

Level of evidence: 1

In contrast to the very limited data on primary prevention in BRCA1 and BRCA2 mutation carriers with tamoxifen, several studies have found a protective effect of tamoxifen on the risk of contralateral breast cancer.[73,74,75] In one study involving approximately 600 BRCA1/2 mutation carriers, tamoxifen use was associated with a 51% reduction in contralateral breast cancer.[73] An update to this report examined 285 BRCA1/2 mutation carriers with bilateral breast cancer and 751 BRCA1/2 mutation carriers with unilateral breast cancer (40% of these patients were included in their initial study). Tamoxifen was associated with a 50% reduction in contralateral breast cancer risk in BRCA1 mutation carriers and a 58% reduction in BRCA2 mutation carriers. Tamoxifen did not appear to confer benefit in women who had undergone an oophorectomy, although the numbers in this subgroup were quite small.[75] Another study involving 160 BRCA1/2 mutation carriers demonstrated that tamoxifen use following treatment of breast cancer with lumpectomy and radiation was associated with a 69% reduction in the risk of contralateral breast cancer.[74] These studies are limited by their retrospective, case-control designs and the absence of information regarding estrogen-receptor status in the primary tumor.

The STAR trial (NSABP-P-2) included more than 19,000 women and compared 5 years of raloxifene with tamoxifen in reducing the risk of invasive breast cancer.[76] There was no difference in incidence of invasive breast cancer at a mean follow-up of 3.9 years; however, there were fewer noninvasive cancers in the tamoxifen group. The incidence of thromboembolic events and hysterectomy was significantly lower in the raloxifene group. Detailed quality of life data demonstrate slight differences between the two arms.[77] Data regarding efficacy in BRCA1 or BRCA2 mutation carriers are not available.

Level of Evidence: 1

Risk-Reducing Mastectomy

In the general population, both subcutaneous mastectomy and simple (total) mastectomy have been used for prophylaxis. Only 90% to 95% of breast tissue is removed with subcutaneous mastectomy.[78] In a total or simple mastectomy, removal of the nipple-areolar complex increases the proportion of breast tissue removed compared with subcutaneous mastectomy. However, some breast tissue is usually left behind with both procedures. The risk of breast cancer following either of these procedures has not been well established.

The effectiveness of risk-reducing mastectomy (RRM) in women with BRCA1 or BRCA2 mutations has been evaluated in several studies. In one retrospective cohort study of 214 women considered to be at hereditary risk by virtue of a family history suggesting an autosomal dominant predisposition, three women were diagnosed with breast cancer after bilateral RRM, with a median follow-up of 14 years.[79] As 37.4 cancers were expected, the calculated risk reduction was 92% (95% CI, 76.6–98.3). In a follow-up subset analysis, 176 of the 214 high-risk women in this cohort study underwent mutation analysis of BRCA1 and BRCA2. Mutations were found in 26 women (18 deleterious, eight variants of uncertain significance). None of those women had developed breast cancer after a median follow-up of 13.4 years.[80] Two of the three women diagnosed with breast cancer after RRM were tested, and neither carried a mutation. The calculated risk reduction among mutation carriers was 89.5% to 100% (95% CI, 41.4%–100%), depending on the assumptions made about the expected numbers of cancers among mutation carriers and the status of the untested woman who developed cancer despite mastectomy. The result of this retrospective cohort study has been supported by a prospective analysis of 76 mutation carriers undergoing RRM and followed prospectively for a mean of 2.9 years. No breast cancers were observed in these women, whereas eight were identified in women undergoing regular surveillance (HR for breast cancer after RRM = 0 [95% CI, 0–0.36]).[81]

The Prevention and Observation of Surgical End Points (PROSE) study group estimated the degree of breast cancer risk reduction after RRM in BRCA1/2 mutation carriers. The rate of breast cancer in 105 mutation carriers who underwent bilateral RRM was compared with that in 378 mutation carriers who did not choose surgery. Bilateral mastectomy reduced the risk of breast cancer after a mean follow-up of 6.4 years by approximately 90%.[82]

Another study evaluated the effectiveness of contralateral RRM in affected women with hereditary breast cancer. In a group of 148 BRCA1 or BRCA2 mutation carriers, 79 of whom underwent RRM, the risk of contralateral cancer was reduced by 91% and was independent of the effect of risk-reducing oophorectomy. Survival was better among women undergoing RRM, but this result was apparently caused by higher mortality due to the index cancer or metachronous ovarian cancer in the group not undergoing surgery.[83] More recently, data from ten European centers on 550 women indicated that RRM was highly effective.[84]

Studies describing histopathologic findings in RRM specimens from women with BRCA1 or BRCA2 mutations have been somewhat inconsistent. In two series, proliferative lesions associated with an increased risk of breast cancer (lobular carcinoma in situ, atypical lobular hyperplasia, atypical ductal hyperplasia, DCIS) were noted in 37% to 46% of women with mutations undergoing either unilateral or bilateral RRM.[85,86,87] In these series, 13% to 15% of patients were found to have previously unsuspected DCIS in the prophylactically removed breast. Among 47 cases of risk-reducing bilateral or contralateral mastectomies performed in known BRCA1 or BRCA2 mutation carriers from Australia, 3 (6%) cancers were detected at surgery.[88] In a study from Sweden among 100 women with a hereditary risk of breast cancer, 50 of whom were BRCA1 or BRCA2 mutation carriers, unsuspected lesions were found in 18 women (3 invasive, 8 in situ, and 7 atypical hyperplasia), 13 of whom were mutation carriers.[89]

These findings were not replicated in a third retrospective cohort study. In this study, proliferative fibrocystic changes were noted in none of 11 bilateral mastectomies from patients with deleterious mutations and in only two of seven contralateral unilateral risk-reducing mastectomies in affected mutation carriers.[90]

Although data are sparse, the evidence to date indicates that while a substantial proportion of women with a strong family history of breast cancer are interested in discussing RRM as a treatment option, uptake varies according to culture, geography, healthcare system, insurance coverage, provider attitudes, and other social factors. For example, in one setting where the providers made one to two field trips to family gatherings for family information sessions and individual counseling, only 3% of unaffected carriers obtained RRM within 1 year of follow-up.[91] Among women at increased risk of breast cancer due to family history, fewer than 10% opted for mastectomy.[92] Selection of this option was related to breast cancer–related worry as opposed to objective risk parameters (e.g., number of relatives with breast cancer). In addition, self-perceived risk has been closely linked to interest in RRM.[92]

Assuming risk reduction in the range of 90%, a theoretical model suggests that for a group of 30-year-old women with BRCA1 or BRCA2 mutations, RRM would result in an average increased life expectancy of 2.9 to 5.3 years.[93] While these data are useful for public policy decisions, they cannot be individualized for clinical care as they include assumptions that cannot be fully tested. Another study of at-risk women showed a 70% time-tradeoff value, indicating that the women were willing to sacrifice 30% of life expectancy in order to avoid RRM.[94] A cost-effectiveness analysis study estimated that risk-reducing surgery (mastectomy and oophorectomy) is cost-effective compared with surveillance with regard to years of life saved, but not for improved quality of life.[95]

In contrast, in a Dutch study of highly motivated women being followed every 6 months at a high-risk center, more than half (51%) of unaffected carriers opted for RRM. Almost 90% of the RRM surgeries were performed within 1 year of DNA testing. In this study, those most likely to have RRM were women younger than 55 years and with children.[96]

The Society of Surgical Oncology has endorsed RRM as an option for women with BRCA1/2 mutations or strong family histories of breast cancer.[97]

Individual psychological factors have an important role in decision-making about RRM by unaffected women. Research is emerging about psychosocial outcomes of RRM. (Refer to the Psychological Aspects of Medical Interventions section of this summary.)

Level of evidence: 3aii

Risk-Reducing Salpingo-Oophorectomy

In the general population, removal of both ovaries has been associated with a reduction in breast cancer risk of up to 75%, depending on parity, weight, and age at time of artificial menopause. (Refer to the PDQ summary on Breast Cancer Prevention for more information.) A Mayo Clinic study of 680 women at various levels of familial risk found that in women younger than 60 years who had bilateral oophorectomy, the likelihood of breast cancers developing was reduced for all risk groups.[98] Ovarian ablation, however, is associated with important side effects such as hot flashes, impaired sleep habits, vaginal dryness, dyspareunia, and increased risk of osteoporosis and heart disease. A variety of strategies may be necessary to counteract the adverse effects of ovarian ablation.

In support of early small studies,[99,100] a retrospective study of 551 women with disease-associated BRCA1 or BRCA2 mutations found a significant reduction in risk of breast cancer (HR 0.47; 95% CI, 0.29–0.77) as well as ovarian cancer (HR 0.04, 95% CI, 0.01–0.16) after risk-reducing salpingo-oophorectomy (RRSO).[101] A prospective single-institution study of 170 women with BRCA1 or BRCA2 mutations showed a similar trend. With RRSO, the HR was 0.15 (95% CI, 0.02–1.31) for ovarian, fallopian tube, or primary peritoneal cancer, and 0.32 (95% CI, 0.08–1.2) for breast cancer; the HR for either cancer was 0.25 (95% CI, 0.08–0.74).[102] A prospective multicenter study of 1,079 women followed for a median of 30 to 35 months found that, while RRSO was associated with reductions in breast cancer risk for both BRCA1 and BRCA2 mutation carriers, the risk reduction was more pronounced in BRCA2 carriers (HR = 0.28; 95% CI, 0.08–0.92).[103] A meta-analysis of all reports of RRSO and breast and ovarian/fallopian tube cancer in BRCA1/BRCA2 mutation carriers confirmed that RRSO was associated with a significant reduction in breast cancer risk (overall HR = 0.49, 95% CI, 0.37-0.65; BRCA1 HR = 0.47, 95% CI, 0.35-0.64; BRCA2 HR = 0.47,95% CI, 0.26-0.84).[104]

Level of evidence: 3aii

Hormone replacement therapy in BRCA1/2 mutation carriers

Refer to the section on Hormone replacement therapy in BRCA1/2 mutation carriers for further information.

Breast conservation therapy for BRCA1/2 mutation carriers

While lumpectomy plus radiation therapy has become standard local-regional therapy for women with early stage breast cancer, its use in women with a hereditary predisposition for breast cancer who do not choose immediate bilateral mastectomy is less clear. Concern about its use, particularly in women with deleterious BRCA1 and BRCA2 mutations, centers around two issues. The first is the potential for an increased rate of ipsilateral cancers in the treated breast. The second is the potential for therapeutic radiation to induce tumors in BRCA1/2 defective cells. Most of the early studies that used family history of breast/ovarian cancer as a surrogate for hereditary risk failed to find an increase in ipsilateral cancers in women treated with breast conservation.[105,106,107,108,109] However, with the availability of clinical genetic testing for BRCA1/2 mutations, treatment outcomes for carriers of deleterious mutations in BRCA1/2 can now be compared with those of noncarriers.

To understand the role of germline BRCA1/2 mutations in determining outcome among women treated conservatively for breast cancer, the records of Ashkenazi Jewish (AJ) women treated with lumpectomy and radiation therapy for invasive breast cancer were reviewed.[110] Archival pathology material was obtained for analysis of the three founder AJ mutations. Deleterious BRCA mutations were found in 56 (11.3%) of the cases. The rate of ipsilateral cancer for founder mutation carriers was 12% at 10 years compared with 8% for women without mutations (not statistically significant). Women with founder AJ mutations were over three times more likely than women without mutations to develop contralateral cancer, 27% versus 8% (P = .0001). The same investigators also described a separate case series of 87 women with BRCA mutations who were treated with breast conserving surgery.[111] They reported a 12.6% rate of ipsilateral breast cancer at a median of 51.8 months, and a 23% rate of contralateral breast cancer at a median of 67.4 months. No control group was included.[111]

A case-control study from the Netherlands compared women with hereditary breast cancer (identified as either BRCA1/2 positive, or by a strong family history) with women without hereditary breast cancer for treatment outcome after breast conservation therapy. Although rates of ipsilateral breast recurrence were similar at 2 years following diagnosis, by 5 years the rate was twice as high in the hereditary cases (14% vs. 7%), and remained twice as high at 10 and 15 years after diagnosis (30% and 49% in the hereditary group, and 16% and 20% in the sporadic group).[112]

A multi-institution retrospective cohort study compared outcomes after breast conserving treatment between women with known BRCA1/2 mutations and those whose family history was not suggestive of a hereditary pattern. At 10 years, overall rates of ipsilateral breast cancer were not significantly different. However, BRCA1/2 mutation status was significantly associated with a risk of ipsilateral breast cancer when those carriers who underwent oophorectomy were removed from the analysis (7.8% for noncarriers vs. 16.3% for carriers). The 10-year estimates for contralateral breast cancer were 3% for noncarriers and 26% for carriers.[74] One study reported an approximately 40% risk of contralateral breast cancer in BRCA mutation carriers, a risk which is reduced by taking tamoxifen or undergoing oophorectomy.[113]

A study of selected patients diagnosed at age 42 years or younger who had undergone conservative therapy were offered genetic testing for BRCA1/2 mutations. Of 127 participants, 22 were found to have deleterious mutations.[114] At a median of 12.7 years of follow-up, the rate of ipsilateral events was 49% in the mutation carriers and 21% in the noncarriers (P = .007). Clinical and pathological features of the ipsilateral tumors were more consistent with second primaries than with local recurrence. Similarly, the rate of contralateral cancers was 42% in the carriers and 9% in the noncarriers (P = .001). This study has been criticized as having an unacceptable rate of ipsilateral events overall, calling into question the adequacy of the local-regional treatment.[115]

As noted above, there is a growing indication that women with BRCA1/2 mutations who are treated conservatively have an increased, not decreased, rate of ipsilateral breast cancer, occurring usually after 5 years of follow-up.

The second concern stems from the emerging understanding of the role of the BRCA genes in DNA repair activities within the cell, and the implication of the loss of these functions for radiation hypersensitivity. Both BRCA1 and BRCA2 are involved in DNA double-strand break repair, and loss of function in these genes could potentially accelerate the rate of cell kill caused by ionizing radiation. Another potentially relevant mechanism is the defect in the G2-M phase checkpoint displayed by BRCA1-deficient cells, which also alters radiation sensitivity.[116] Furthermore, murine models of Brca1- and Brca2-deficient mice have demonstrated evidence of hypersensitivity to ionizing radiation.[18,117] Clinical manifestations of these findings could include:

1. An increased response to adjuvant radiation therapy with a decrease of in-breast recurrence rates.
2. An increase in ipsilateral and contralateral breast cancers secondary to genetic instability.
3. An increase in radiation-related toxicity.

In one study, the rate of local recurrence among women with strong family histories who were treated with lumpectomy was highest when radiation was omitted, suggesting that these tumors are radiosensitive.[107] Rates of contralateral disease are consistently elevated in this population, but are equal for women treated with conservative therapy and for those who chose mastectomy without radiation, indicating that the increased risk is due to the mutation, not the exposure to radiation. And finally, studies have failed to find an increase in either early acute radiation tissue reactions or late radiation reactions to the skin, underlying tissue or bone.[118,119,120]

These data are consistent with a model in which hereditary BRCA1/2 cancers are sterilized by radiation therapy equally well, but due to the underlying genetic predisposition, the increased risk of second primaries in the treated breast remains. The findings of a significantly increased risk of contralateral breast cancer in this population is consistent across studies, and increasingly women with BRCA1/2 mutations are considering bilateral mastectomy at the time of first diagnosis of breast cancer, regardless of stage. Finally, there is no evidence for an increase in radiation toxicity among BRCA1/2 mutation carriers.

Level of evidence: 3di

Role of BRCA1 and BRCA2 in response to chemotherapy

A small but growing body of preclinical and clinical literature suggests a differential response of BRCA-related breast cancers to systemic chemotherapy. This is based on the emerging understanding of the functions of these genes in response to DNA damage and mitotic spindle machinery control. As several chemotherapeutic agents target either DNA or mitotic spindle structural integrity, the lack of BRCA functions could alter response to these agents. The absence of BRCA-mediated DNA repair could potentially increase sensitivity to these agents, which induce DNA breaks. On the other hand, the failure to activate cell cycle checkpoints in response to DNA damage could allow damaged tumor cells to avoid apoptosis and survive, leading to chemotherapy resistance. In the case of spindle poisons, BRCA1 has a role in the detection of microtubule disruption and induces apoptosis to prevent aberrant mitosis. Its absence could circumvent this mitotic regulation and thereby enhance sensitivity to spindle poisons. Several in vitro studies have begun to explore potential mechanisms for a differential response of BRCA-related breast cancers to several classes of chemotherapy. There are no clinical data at this time indicating that BRCA-associated cancers should be treated with different chemotherapy than non-BRCA-associated cancers.

Cell lines with inducible expression of BRCA1 were generated to explore its potential role in the cellular response to various chemotherapeutic agents.[121] In the presence of the antimicrotubule agents Taxol and vincristine, expression of BRCA1 resulted in a significant increase in cell death associated with an acute arrest in G2/M, suggesting that BRCA1 expression may be an important mediator of response to antimicrotubule agents by preventing progression of the cell into mitosis. BRCA1-deficient tumors, therefore, may exhibit resistance to this class of drugs.

The ability of BRCA1 to sensitize breast cancer cell lines to G2/M arrest in response to antimicrotubule agents was confirmed in a second study.[122] In contrast, BRCA1 induced resistance to DNA-damaging agents that induce double-strand breaks in DNA. Both of these opposing effects were mediated by inhibition or induction of apoptosis.

It has been shown that cell lines deficient in BRCA1 are defective in homology-directed chromosomal break repair, and highly sensitive to the interstrand cross-linking agent mitomycin-C.[123] Additional evidence supporting a role of BRCA1 in response to DNA-damaging drugs is seen in cisplatinum-resistant breast and ovarian cancer cell lines, in which BRCA1 is overexpressed and DNA repair is enhanced.[124]

Decreasing expression of BRCA1 in cell lines has been associated with increased sensitivity to cisplatinum and etoposide, and resistance to the tubule-damaging agents Taxol and vincristine.[125] Resistance was linked to transcriptional modifications in the JNK pathway which mediates apoptosis. Increased sensitivity to cisplatinum was associated with a time-dependent and dose-dependent increase in apoptosis in a mouse mammary epithelial cell line.[126] Another mechanism suggested for increased cisplatinum sensitivity in BRCA mutant cells is the role of both BRCA1 and BRCA2 in the promotion of subnuclear Rad51 foci for DNA repair.[127] A cell culture model was used to study the interaction of cyclin-dependent kinase 2 (CDK2) inhibition and BRCA1 deficiency.[128] CDK2 is a serine/threonine kinase that has a role in cell cycle control. Inhibitors of CDK2 cause delays in DNA damage signaling. CDK2 inhibition was fourfold more toxic in the presence of BRCA1 mutations, suggesting that CDK2 inhibition may be a sensitive target in patients with BRCA1 mutations. Another specific pathway to exploit in BRCA1/2 deficient tumors is the poly (ADP-ribose) polymerase (PARP) pathway. PARP is active in the repair of double-strand breaks by homologous recombination. In vitro studies have shown that PARP inhibition kills BRCA mutant cells with high specificity. This specificity has not yet been demonstrated in vivo,[129] although phase I studies of PARP inhibitors in combination with chemotherapeutic agents are underway.

Overall, the preclinical data supports the conclusion that BRCA1 inhibits apoptosis after treatment with DNA-damaging agents, and its absence promotes apoptosis leading to increased sensitivity. In contrast, BRCA1 promotes apoptosis after exposure to spindle poisons and its absence supports survival of cells damaged by spindle poisons and thereby confers drug resistance.[130] Similarly, an animal model of Brca2 deficiency in murine small intestine showed a reduction in clonogenic survival after exposure to either cisplatinum or mitomycin C.[131]

Evidence of the role of BRCA1/2 mutations in human studies is very preliminary. Among 38 women treated with neoadjuvant therapy for stages I-III breast cancer, those with BRCA1/2 mutations were significantly more likely to achieve a clinical and pathological complete response, independent of clinical stage.[132] Another small neoadjuvant trial treated ten BRCA1/2 mutation carriers who had stage I to stage III breast cancer with four cycles of single-agent cisplatin prior to mastectomy. At the time of the surgery, nine of the ten patients had a complete pathologic response.[133]

Thus the preclinical and clinical data are consistent with the emerging understanding of BRCA1 function in DNA-damage response as well as cell cycle regulation. While these findings raise the possibility that germline status may influence treatment choices, there is insufficient evidence at this time to support treating mutation carriers with different regimens.

Ovarian Cancer

Screening

Refer to the PDQ summary on Ovarian Cancer Screening for information on screening in the general population, and to the PDQ summary Cancer Genetics Overview for information on levels of evidence related to screening and prevention. The latter also outlines the five requirements that must be met before it is considered appropriate to screen for a particular medical condition as part of routine medical practice.

Clinical Examination

In the general population, clinical examination of the ovaries has neither the specificity nor the sensitivity to reliably identify early ovarian cancer. No data exist regarding the benefit of clinical examination of the ovaries (bimanual pelvic examination) in women at inherited risk of ovarian cancer.

Level of evidence: None assigned

Transvaginal Ultrasound

In the general population, transvaginal ultrasound (TVUS) appears to be superior to transabdominal ultrasound in the preoperative diagnosis of adnexal masses. Both techniques have lower specificity in premenopausal women than in postmenopausal women, due to the cyclic menstrual changes in premenopausal ovaries (e.g., transient corpus luteum cysts) that can cause difficulty in interpretation. A screening trial of TVUS in 25,327 asymptomatic women aged 50 years or older or aged 25 years or older and with a family history of ovarian cancer in a first- or second-degree relative was reported. Of these, 364 (1.4%) women had persistent ovarian abnormalities and underwent surgery. Approximately 88% (320 of 364) of the lesions were benign. Thirty-five women had primary invasive ovarian cancer, nine had low malignant potential tumors, and seven had cancers that were metastatic to the ovary.[134]

Data are limited regarding the potential benefit of transvaginal ultrasound in screening women at inherited risk of ovarian cancer. A number of retrospective studies have reported their experience with ovarian cancer screening in high-risk women using TVUS with or without CA 125.[7,135,136,137,138,139,140,141,142,143,144,145] However, there is little uniformity in the definition of high-risk criteria and compliance with screening, and in whether cancers detected were incident or prevalent. One of the largest reported studies included 888 BRCA1/2 mutation carriers who were screened annually with TVUS and CA 125. Ten women developed ovarian cancer, with five of ten developing interval cancers with normal screening results within 3 to 10 months before diagnosis. Five of the ten ovarian cancers were screen-detected incident cases, with normal screening results within 6 to 14 months before diagnosis. Of these five cases, four were stage IIIB or IV.[135]

Other studies also demonstrate that the ovarian cancers detected by screening are frequently advanced stage, and interval cancers can develop. Another study evaluated 383 high-risk women (152 BRCA1/2 mutation carriers) with annual TVUS and CA 125.[138] Abnormal screening results were noted in 74 women (19.3%), but these resolved spontaneously in 47 women (63.5%). Of the 20 women undergoing exploratory surgery, only one had cancer, which proved to be a breast cancer metastatic to the ovary. No epithelial ovarian cancers were found as a result of screening. A similar study reported the results of annual TVUS and CA 125 in a cohort of 312 high-risk women (152 BRCA1/2 mutation carriers).[137] Of the four cancers that were detected due to abnormal TVUS and CA 125, all four patients were symptomatic, and three had advanced-stage disease. Annual screening of BRCA1/2 mutation carriers with pelvic ultrasound, TVUS, and CA 125 failed to detect early-stage ovarian cancer among 241 BRCA1/2 mutation carriers in a study from the Netherlands.[146] Finally, a study of 1,100 moderate- and high-risk women who underwent annual TVUS and CA 125 reported that ten of 13 ovarian tumors were detected due to screening. Only five of ten were stage I or II.[136] There are limited data related to the efficacy of semiannual screening with TVUS and CA 125.[7,144]

Level of evidence: 4

Serum CA 125

Serum CA 125 screening for ovarian cancer in high-risk women has been evaluated in combination with TVUS in a number of retrospective studies, as described in the previous section.[7,135,136,137,138,139,140,141,142,143,144]

The National Institutes of Health (NIH) Consensus Statement on Ovarian Cancer recommended against routine screening of the general population for ovarian cancer with serum CA 125. The NIH Consensus Statement did, however, recommend that women at inherited risk of ovarian cancer undergo TVUS and serum CA 125 screening every 6 to 12 months, beginning at age 35 years.[147] The Cancer Genetics Studies Consortium task force has recommended that female carriers of a deleterious BRCA1 mutation undergo annual or semiannual screening using TVUS and serum CA 125 levels, beginning at age 25 to 35 years.[9] Both recommendations are based solely on expert opinion and best clinical judgment.

Level of evidence: 5

In the United States, the National Cancer Institute (NCI) is conducting a large controlled clinical trial in which 74,000 women were randomized to regular medical care or research-based screening for lung, colorectal, and ovarian cancer. The ovarian cancer screening consisted of serum CA 125 (baseline, and annually for 6 years) and TVUS (baseline, and annually for 4 years).[148] NCI's Clinical Genetics Branch, the Gynecologic Oncology Group, and the Cancer Genetics Network are collaborating on a prospective study (GOG-0199) of women at increased genetic risk of ovarian cancer in which risk-reducing surgery and a novel CA 125-based screening strategy are being evaluated.

The PDQ Cancer Screening and Prevention Board has reviewed the evidence related to the efficacy of pelvic examination, TVUS and serum CA 125 screening for ovarian cancer IN THE GENERAL POPULATION and concluded "There is inadequate evidence to determine whether routine screening for ovarian cancer…. would result in a decrease in mortality from ovarian cancer." (Refer to the Ovarian Cancer Screening summary for more information.)

Level of evidence: 5

Other Candidate Ovarian Cancer Biomarkers

The need for effective ovarian cancer screening is particularly important for women carrying mutations in BRCA1 and BRCA2, and the mismatch repair genes (e.g., MLH1, MSH2, MSH6, PMS2), disorders in which the risk of ovarian cancer is high. There is a special sense of urgency for BRCA1 mutation carriers, in whom cumulative lifetime risks of ovarian cancer may exceed 40%.

Thus, it is expected that many new ovarian cancer biomarkers (either singly or in combination) will be proposed as ovarian cancer screening strategies during the next 5 to 10 years. While this is an active area of research with a number of promising new biomarkers in early development, IT IS IMPORTANT TO ACKNOWLEDGE THAT, AT PRESENT, NONE OF THESE BIOMARKERS ALONE OR IN COMBINATION HAVE BEEN SUFFICIENTLY WELL STUDIED TO JUSTIFY THEIR ROUTINE CLINICAL USE FOR SCREENING PURPOSES, either in the general population or in women at increased genetic risk.

Before addressing information related to emerging ovarian cancer biomarkers, it is important to consider the several steps that are required to develop and, more importantly, validate a new biomarker. One useful framework is that published by NCI Early Detection Research Network investigators.[149] They indicated that the goal of a cancer-screening program is to detect tumors at an early stage so that treatment is likely to be successful. The gold standard by which such programs are judged is whether the death rate from the cancer for which screening is performed is reduced among those being screened. In addition, the screening test must be sufficiently noninvasive and inexpensive to allow widespread use in the population to be screened. Maintaining high test specificity (i.e., few false-positive results) is essential for a population screening test, because even a low false-positive rate results in many people having to undergo unnecessary and costly diagnostic procedures and psychological stress. It is likely that the use of several such cancer biomarkers in combination will be required for a screening test to be both sensitive and specific.

Furthermore, a clinically useful test must have a high PPV (a parameter derived from sensitivity, specificity and disease prevalence in the screened population). Practically speaking, a biomarker with a PPV of 10% implies that ten surgical procedures would be required to identify one case of ovarian cancer; the remaining nine surgeries would represent false-positive test findings. In general, the ovarian cancer research community considers biomarkers with a PPV less than 10% to be clinically unacceptable, given the morbidity related to bilateral salpingo-oophorectomy. Finally, it is important to keep in mind that while novel biomarkers may be present in the sera of women with advanced ovarian cancer (which comprise the vast majority of cases analyzed in the early phases of biomarker development), they may or may not be detectable in women with early stage disease, which is essential if the screening test is to be clinically useful.

It has been suggested that there are five general phases in biomarker development and validation:

Phase I — Preclinical exploratory studies

  • Identify potentially discriminating biomarkers.
  • Usually done by comparing gene over- or under-expression in tumor compared with normal tissue.
  • Since many exploratory analyses in large numbers of genes are performed at this stage, one or more may seem to have good discriminating ability between cancers and normal tissue by random chance alone.

Phase 2 — Clinical assay development for clinical disease

  • Develop a clinical assay that can be obtained on noninvasively obtained samples (e.g., a blood specimen).
  • Often the test targets the protein product of one of the genes found to be of interest in phase I.
  • The goal is to describe the performance characteristics of the assay for distinguishing between subjects with and without cancer. At this point, the assay should be in its final configuration and remain stable throughout the following phases.
  • IMPORTANT: Since the case subjects in a phase 2 study ALREADY HAVE CANCER, with assay results obtained at the time of disease diagnosis, one cannot determine if disease can be detected early with a given biomarker.

Phase 3 — Retrospective longitudinal repository studies

  • Compare clinical specimens collected from cancer case subjects before their clinical diagnosis with specimens from subjects who have not developed cancer.
  • Evaluate, as a function of time before clinical diagnosis, the biomarker's ability to detect preclinical disease.
  • Define the criteria for a positive screening test in preparation for phase 4.
  • Explore the influence of other patient characteristics (e.g., age, gender, smoking status, medication use) on the ability of the biomarker to discriminate between those with and without preclinical disease.

Phase 4 — Prospective screening studies

  • Determine the operating characteristics of the biomarker-based screening test in a population for which the test is intended.
  • Measure the detection rate (number of abnormal tests among all those with the disease) and the false-positive rate (the number of abnormal tests among all those who do not have the disease).
  • Evaluate whether the cancers detected by the test are being found at an early stage, a point at which treatment is more likely to be curative.
  • Assess whether the test is acceptable in a population of persons for whom it is intended. Will subjects comply with the test schedule and results?

Phase 5 — Cancer control studies

  • Ideally, randomized controlled clinical trials in clinically relevant populations, in which one arm is subjected to screening and appropriate intervention if screen-positive, while the other arm is not screened.
  • Determine whether the death rate of the cancer being screened for is reduced among those who use the screening test.
  • Obtain information about the costs of screening and treatment of screen-detected cancers.

Finally, for a validated biomarker test to be considered appropriate for use in a particular population, it must have been evaluated in that specific population without prior selection of known positives and negatives. In addition, the test must demonstrate clinical utility, that is, a positive net balance of benefits and risks associated with the application of the test. These may include improved health outcomes, as well as net psychosocial and economic benefits.[150]

Ovarian cancer poses a unique challenge relative to the potential impact of false-positive test results. There are no reliable noninvasive diagnostic tests for early stage disease, and clinically-significant early stage cancer may not be grossly visible at the time of exploratory surgery.[151] Consequently, it is likely that some patients will only be reassured that their abnormal test does not indicate the presence of cancer by having their ovaries and fallopian tubes surgically removed and examined microscopically. High test specificity (i.e., a very low false-positive rate) is required to avoid unnecessary surgery and induction of premature menopause in false positive women.

Variations on CA 125

CA 125 Plus an Ovarian Cancer Symptom Index

An ovarian cancer symptom index for predicting the presence of cancer was evaluated in 75 cases and 254 high-risk controls (BRCA mutation carriers or women with a strong family history of breast and ovarian cancer).[152] Women had a positive symptom index if they reported any of the predefined symptoms (bloating or increase in abdominal size, abdominal or pelvic pain, and difficulty eating or feeling full quickly) more than 12 times per month occurring only within the prior 12 months. CA 125 values greater than 30 U/mL were considered abnormal. The symptom index independently predicted the presence of ovarian cancer, after controlling for CA 125 levels (p < 0.05). The combination of an elevated CA 125 and a positive symptom index correctly identified 89.3% of the cases. The symptom index correlated with the presence of cancer in 50% of the affected women who did not have elevated CA 125 levels, but 11.8% of the high-risk controls without cancer also had a positive symptom index. The authors suggested that a composite index including both CA 125 and the symptom index had better performance characteristics than either test used alone, and that this strategy might be used as a first screen in a multi-step screening program. Additional test performance validation and determination of clinical utility are required in unselected screening populations.

Level of evidence: 5

Risk of Ovarian Cancer Algorithm

A novel modification of CA 125 screening is based on the hypothesis that rising CA 125 levels over time may provide better ovarian cancer screening performance characteristics than simply classifying CA 125 as normal or abnormal, based on an arbitrary cut-off value. This has been implemented in the form of the Risk of Ovarian Cancer Algorithm (ROCA), an investigational statistical model that incorporates serial CA 125 test results and other covariates into a computation which produces an estimate of the likelihood that ovarian cancer is present in the screened subject. The first report of this strategy – based on reanalysis of 5,550 average-risk women from the Stockholm Ovarian Cancer screening trial – suggested that ovarian cancer cases and controls could be distinguished with 99.7% sensitivity, 83% specificity, and a PPV of 16%. That PPV represents an eight-fold increase over the 2% PPV reported with a single measure of CA 125.[153] This report was followed by applying the risk of ovarian cancer algorithm (ROCA) to 33,621 serial CA 125 values obtained from the 9,233 average-risk postmenopausal women in a prospective British ovarian cancer screening trial.[154] The area under the receiver operator curve increased from 84% to 93% (P = 0.01) for ROCA compared with a fixed CA 125 cutoff. These observations represented the first evidence that preclinical detection of ovarian cancer might be improved using this screening strategy. A prospective study of 13,000 normal volunteers aged 50 years and older in England used serial CA 125 values and the ROCA to stratify participants into low, intermediate and elevated risk subgroups.[155] Each had its own prescribed management strategy, including TVUS and repeat CA 125 either annually (low risk) or at 3 months (intermediate risk). Using this protocol, ROCA was found to have a specificity of 99.8% and a PPV of 19%.

Currently, there are two prospective trials underway in England which utilize the ROCA: the United Kingdom Collaborative Trial of Ovarian Cancer Screening targets normal-risk women randomized either to (1) no screening, (2) annual ultrasound or (3) multimodal screening using the ROCA (n = 202,638; accrual completed; follow-up ends in 2011); and the U.K. Familial Ovarian Cancer Screening Study which targets high-risk women (accrual ongoing). There are also two high-risk cohorts using the ROCA under evaluation in the United States: the Cancer Genetics Network ROCA Study (n = 2,500; follow-up complete; analysis underway), and the Gynecologic Oncology Group Protocol 199 (GOG-0199) (n = 1,575 screening subjects; enrollment complete; follow-up ends in late 2011).[156] Thus, additional data regarding the utility of this currently investigational screening strategy will become available within the next few years.

Level of evidence: 4

Miscellaneous New Markers

A wide array of new candidate ovarian cancer biomarkers has been described during the past decade, including HE4; mesothelin; kallekreins 6, 10, and 11; osteopontin; prostasin; M-CSF ;OVX1; lysophosphatidic acid; vascular endothelial growth factor (VEGF) B7-H4; and interleukins 6 and 8, to name just a few.[157,158,159] These have been singly studied, in combination with CA 125, or in various other permutations. Most of the study populations are relatively small and comprise highly-selected known ovarian cancer cases and healthy controls of the type evaluated in early biomarker development phases I and II. Results have not been consistently replicated in multiple studies; presently, none are considered ready for widespread clinical application.

Level of evidence: 5

Proteomics

Initially, mass spectroscopy of serum proteins was combined with complex analytic algorithms to identify protein patterns that might distinguish between ovarian cancer cases and controls.[160] This approach assumed that pattern recognition alone would be sufficient to permit such discrimination, and that identification of the specific proteins responsible for the patterns identified was not required. Subsequently, this strategy has been modified, using similar laboratory tools, to identify finite numbers of specific known serum markers that may be used in place of, or in conjunction with, CA 125 measurements for the early detection of cancer.[161] These studies [159,162] have generally been small case-control studies that are limited by sample size and the number of early-stage cancer cases included. Further evaluation is needed to determine whether any additional markers identified in this fashion have clinical utility for the early detection of ovarian cancer in the unselected clinical population of interest.

Level of evidence: 5

Multiplex Assays

Because individual biomarkers have not met the criteria for an effective screening test, it has been suggested that it may be necessary to combine multiple ovarian cancer biomarkers in order to obtain satisfactory screening test results. This strategy was employed to quantitatively analyze six serum biomarkers (leptin, prolactin, osteopontin, insulin-like growth factor II, macrophage inhibitory factor, and CA 125), using a multiplex, bead-based platform.[163] A similar assay was available commercially under the trade name OvaSure™ until its voluntary withdrawal from the market by the manufacturer.[Response to FDA Warning Letter]

The cases in this study were newly-diagnosed ovarian cancer patients who had blood collected just prior to surgery: 36 were stage I/II; 120 were stage III/IV. The controls were healthy age-matched individuals who had not developed ovarian cancer within 6 months of blood draw. Neither cases nor controls in this study were well-characterized regarding their familial/genetic risk status, but they have been suggested to comprise a high-risk population.

First, 181 controls and 113 ovarian cancer cases were tested to determine the initial panel of biomarkers that best discriminated between cases and controls (training set). The resulting panel was applied to an additional 181 controls and 43 ovarian cancer cases (test set). Pooling both early and late stage ovarian cancer across the combined training and test sets, performance characteristics were reported as a sensitivity of 95.3% and a specificity of 99.4%, with a PPV of 99.3% and a NPV of 99.2%, using a formula that assumed an ovarian cancer prevalence of about 50%, as seen in the highly-selected research population. In order to avoid biases which may make test performance appear to be better than it really is, it is worth noting that combining training and test populations in analyses of this sort is generally not recommended.[164]

However, the most appropriate prevalence to use is the disease prevalence in the unselected population to be screened. The prevalence of ovarian cancer in the general population is 1 in 2,500. In a recently published correction to their manuscript,[163] the authors assumed that the prevalence of ovarian cancer in the screened population was 1/2,500 (0.04%) and recalculated the PPV to be only 6.5%, and on that basis the investigators have retracted their claim that this test is suitable for population screening. If this test were used in patients at increased risk of ovarian cancer, the actual prevalence in such a target population is likely to be higher than that observed in the general population, but well below the assumed 50% figure used in the published analysis. This revised PPV of 6.5% indicates that approximately 1 in 15 women with a positive test would in fact have ovarian cancer, and only a fraction of those with ovarian cancer would be stages I or II. The remaining 14 positive tests would represent false-positives, and these women would be at risk of exposure to needless anxiety and potentially morbid diagnostic procedures, including bilateral salpingo-oophorectomy.

Viewed in the context of the criteria previously described,[149] this assay would be classified as phase 2 in its development. While this appears to be a promising avenue of ovarian cancer screening research, additional validation is required, particularly in an unselected population representative of the clinical screening population of interest. A recent position statement by the Society of Gynecologic Oncologists regarding this assay indicated "it is our opinion that additional research is needed to validate the test's effectiveness before offering it to women outside of the context of a research study conducted with appropriate informed consent under the auspices of an Institutional Review Board."

Level of evidence: 5

Risk modification

Refer to the PDQ summary on Prevention of Ovarian Cancer for information on prevention in the general population, and to the PDQ summary Cancer Genetics Overview for information on levels of evidence related to screening and prevention.

Reproductive Factors

It has been suggested that incessant ovulation, with repetitive trauma and repair to the ovarian epithelium, increases the risk of ovarian cancer. In epidemiologic studies in the general population, physiologic states that prevent ovulation have been associated with decreased risk of ovarian cancer. It has also been suggested that chronic overstimulation of the ovaries by luteinizing hormone (LH) plays a role in ovarian cancer pathogenesis.[165] Most of these data derive from studies in the general population, but some information suggests the same is true in women at high risk due to genetic predisposition.

Pregnancy

Among the general population, parity decreases the risk of ovarian cancer by 45% compared with nulliparity. Subsequent pregnancies after the first appear to decrease ovarian cancer risk by 15%.[166] Earlier studies of women with BRCA1/2 mutations showed that parity decreases the risk of ovarian cancer.[167,168] In a large case-control study, parity was associated with a significant reduction in ovarian cancer risk in women with BRCA1 mutations, OR 0.67 (CI 0.46–0.96).[169] For each birth, BRCA1 mutation carriers had an OR of 0.87 (CI 0.79–0.95). In this same study, parity was associated with an increase in ovarian cancer risk in BRCA2 mutation carriers; however, there was no significant trend for each birth, OR 1.08 (0.90–1.29). Further studies are necessary to define the association of parity and risk of ovarian cancer in BRCA2 mutation carriers, but for BRCA1 carriers, each live birth significantly decreases risk of ovarian cancer, as it does in sporadic ovarian cancer.

Lactation and Tubal Ligation

In the general population, breast feeding is associated with a decrease in ovarian cancer risk.[170] In BRCA mutation carriers, data are limited. One study found no protective effect with breast feeding.[167] A case-control study among women with BRCA1 or BRCA2 mutations demonstrates a significant reduction in risk of ovarian cancer (OR = 0.39) for women who have had a tubal ligation. This protective effect was confined to those women with mutations in BRCA1 and persists after controlling for oral contraceptive pill use, parity, history of breast cancer, and ethnicity.[171] A case-control study of ovarian cancer in Israel found a 40% to 50% reduced risk of ovarian cancer among women undergoing gynecologic surgeries (tubal ligation, hysterectomy, unilateral oophorectomy, ovarian cystectomy, excluding bilateral oophorectomy).[172] The mechanism of protection is uncertain. Proposed mechanisms of action include decreased blood flow to the ovary, resulting in interruption of ovulation and/or ovarian hormone production; occlusion of the fallopian tube, thus blocking a pathway for potential carcinogens; or a reduction in the concentration of uterine growth factors that reach the ovary.[173] (Refer to the PDQ summary on Prevention of Ovarian Cancer for information relevant to the general population.)

Oral Contraceptives

Oral contraceptives have been shown to have a protective effect against ovarian cancer in the general population.[174] Several studies including a large, multicenter case-control study showed a protective effect,[55,169,171,175,176] while one population-based study from Israel failed to demonstrate a protective effect.[168]

A multicenter study of 799 ovarian cancer patients with BRCA1 or BRCA2 mutations, and 2,424 control patients without ovarian cancer but with a BRCA1 or BRCA2 mutation, showed a significant reduction in ovarian cancer risk with use of oral contraceptives, OR 0.56 (CI 0.45–0.71). Compared to never use of oral contraceptives, duration up to one year was associated with an OR of 0.67 (0.50–0.89). The OR for each year of oral contraceptive use was 0.95 (CI 0.92–0.97) with a maximum observed protection at 3 years to 5 years of use. This study included women from a prior study by the same authors and confirmed the results of that prior study.[55] A population-based case-control study of ovarian cancer did not find a protective benefit of oral contraceptive use in BRCA1 or BRCA2 mutation carriers, (OR = 1.07 for =5 years of use), though they were protective, as expected, among noncarriers (OR = 0.53 for =5 years of use).[168] A small population-based case-control study of 36 BRCA1 mutation carriers, however, observed a similar, protective effect in both mutation carriers and noncarriers (OR = approximately 0.5).[176] Finally, a multicenter study of subjects drawn from numerous registries observed a protective effect of oral contraceptives among the 147 BRCA1 or BRCA2 mutation carriers with ovarian cancer compared with the 304 matched mutation carriers without cancer (OR = 0.62 for =6 years of use).[175]

As noted under oral contraceptives in the Breast Cancer Risk Modification section of this summary, there are conflicting data regarding their effect on breast cancer risk, with some retrospective case-control studies suggesting that oral contraceptive use increases the risk of breast cancer in women at inherited risk of breast cancer,[50,177] including BRCA1 mutation carriers,[51] while a population-based study found a reduced risk among BRCA1 mutation carriers.[53]

Level of evidence: 3

Risk-Reducing Salpingo-Oophorectomy

Numerous studies have found that women at inherited risk of breast and ovarian cancer have a decreased risk of ovarian cancer following risk-reducing salpingo-oophorectomy (RRSO). A retrospective study of 551 women with disease-associated BRCA1 or BRCA2 mutations found a significant reduction in risk of breast cancer (HR = 0.47; 95% CI, 0.29–0.77) and ovarian cancer (HR = 0.04; 95% CI, 0.01–0.16) after bilateral oophorectomy.[101] A prospective single-institution study of 170 women with BRCA1 or BRCA2 mutations showed a similar trend.[102] With oophorectomy, the HR was 0.15 (95% CI, 0.02–1.31) for ovarian, fallopian tube, or primary peritoneal cancer, and 0.32 (95% CI, 0.08–1.2) for breast cancer; the HR for either cancer was 0.25 (95% CI, 0.08–0.74). A prospective multicenter study of 1,079 women followed for a median of 30 to 35 months found that RRSO is highly effective in reducing ovarian cancer risk for BRCA1 and BRCA2 mutation carriers. This study also showed that while RRSO was associated with reductions in breast cancer risk for both BRCA1 and BRCA2 mutation carriers, the breast cancer risk reduction was more pronounced in BRCA2 carriers (HR = 0.28; 95% CI, 0.08–0.92).[103] In a case-control study in Israel, bilateral oophorectomy was associated with reduced ovarian/peritoneal cancer risks (OR = 0.12; 95% CI, 0.06–0.24).[172] A meta-analysis of all reports of RRSO and breast and ovarian/fallopian tube cancer in BRCA1/BRCA2 mutation carriers confirmed that RRSO was associated with a significant reduction in risk of ovarian or fallopian tube cancer (HR = 0.21, 95% CI, 0.12–0.39). The study also found a significant reduction in risk of breast cancer (overall HR = 0.49, 95% CI, 0.37–0.65; BRCA1 HR = 0.47, 95% CI, 0.35–0.64; BRCA2 HR = 0.47, 95% CI, 0.26–0.84).[104]

In addition to a reduction in risk of ovarian and breast cancer, RRSO may also significantly improve overall survival, as well as breast and ovarian cancer specific survival. A prospective cohort study of 666 women with germline mutations in BRCA1 and BRCA2 found an HR for overall mortality of 0.24 (95% CI, 0.08–0.71) in women who had RRSO compared with women who did not.[178] This study provides the first evidence to suggest a survival advantage among women undergoing RRSO.

Studies on the degree of risk reduction afforded by RRSO have begun to clarify the spectrum of occult cancers discovered at the time of surgery. Primary fallopian tube cancers, primary peritoneal cancers, and occult ovarian cancers have all been reported. Several case series have reported a prevalence of malignant findings among mutation carriers undergoing risk-reducing oophorectomy to be in the range of 2.3% to 33%, with a median age of the affected women in the range of 42 to 48 years.[179,180,181,182,183] The wide variation in prevalence is likely due to differences in surgical technique and pathologic handling of the tissues. In addition to occult cancers, premalignant lesions have also been described in fallopian tube tissue removed for prophylaxis. In one series of 12 women with BRCA1 mutations undergoing risk-reducing surgery, 11 had hyperplastic or dysplastic lesions identified in the tubal epithelium. In several of the cases the lesions were multifocal.[184] These pathologic findings are consistent with the identification of germline BRCA1 and BRCA2 mutations in women affected with both tubal and primary peritoneal cancers.[183,185,186,187,188,189,190] One study suggests a causal relationship between early tubal carcinoma, or tubal intraepithelial carcinoma, and subsequent invasive serous carcinoma of the fallopian tube, ovary or peritoneum.[191]

These findings support the inclusion of fallopian tube cancers, which account for less than 1% of all gynecologic cancers in the general population, as a component of hereditary ovarian cancer, and underscore the need for the routine collection of peritoneal washings and careful pathologic evaluation of all tissue obtained at the time of risk-reducing surgery. They also raise questions about the optimal surgical approach to provide maximal cancer risk reduction. Some surgeons have recommended hysterectomy in addition to RRSO to remove the remnant of fallopian tube tissue embedded in the uterus, but there is no consensus on this issue, and most, if not all, fallopian tubes cancers appear to arise in the more distal segments of the tube.[183] Several studies have examined whether BRCA1 or BRCA2 mutation carriers are at increased risk of endometrial cancer.[192,193,194,195,196] While case reports and smaller studies suggested an association between BRCA mutations and a specific histology of endometrial cancer called uterine papillary serous cancer,[193] other studies have not found an increased risk of either uterine papillary serous cancer or endometrial cancer in BRCA1 or BRCA2 mutation carriers.[194,195] One cohort study of 857 BRCA1 or BRCA2 mutation carriers reported an increased endometrial cancer risk but found that this risk was largely due to tamoxifen use associated with breast cancer treatment.[196] Therefore, in the absence of tamoxifen use or other underlying uterine or cervical problems, hysterectomy is not a necessary component of risk–reducing salpingo-oophorectomy.

The peritoneum, however, appears to remain at low risk for the development of a Mullerian-type adenocarcinoma, even after oophorectomy.[197,198,199,200,201] Of the 324 women from the Gilda Radner Familial Ovarian Cancer Registry who underwent risk-reducing oophorectomy, six (1.8%) subsequently developed primary peritoneal carcinoma. No period of follow-up was specified.[202] Among 238 individuals in the Creighton Registry with BRCA1/2 mutations who underwent risk-reducing oophorectomy, five subsequently developed intra-abdominal carcinomatosis (2.1%). Of note, all five of these women had BRCA1 mutations.[203] A study of 1,828 women with a BRCA1 or BRCA2 mutation found a 4.3% risk of primary peritoneal cancer at 20 years after RRSO.[204]

Given the current limitations of screening for ovarian cancer and the high risk for the disease in BRCA1 and BRCA2 mutation carriers, NCCN Guidelines recommend RRSO between the ages of 35 and 40 years or upon completion of childbearing, as an effective risk-reduction option. Optimal timing of RRSO must be individualized, but evaluating a woman's risk for ovarian cancer based on mutation status can be helpful in the decision-making process. In a large study of U.S. BRCA1 and BRCA2 families, age-specific cumulative risk of ovarian cancer at age 40 years was 4.7% for BRCA1 mutation carriers and 1.9% for BRCA2 mutation carriers.[205] In a combined analysis of 22 studies of BRCA1 and BRCA2 mutation carriers, risk of ovarian cancer for BRCA1 mutation carriers increases most sharply between the ages of 40 years and 50 years, while for BRCA2 mutation carriers the risk is low before age 50 years, but increases sharply between the ages of 50 years and 60 years.[206] In a population-based study of BRCA mutations in ovarian cancer patients, patients with BRCA2 mutations had a significantly later age of onset than patients with BRCA1 mutations (57.3 years [40-72] vs. 52.6 [31-78]).[207] In summary, women with BRCA1 mutations may consider RRSO for ovarian cancer risk reduction at a somewhat earlier age than women with BRCA2 mutations; however, women with BRCA2 mutations may still consider early RRSO for breast cancer risk reduction.

For women who are premenopausal at the time of surgery, the symptoms of surgical menopause (e.g., hot flashes, mood swings, weight gain, and genitourinary complaints) can cause a significant impairment in their quality of life. To reduce the impact of these symptoms, providers have often prescribed a time-limited course of systemic HRT after surgery. Refer to the section on Hormone replacement therapy in BRCA1/2 mutation carriers for further information.

Studies have examined the effect of RRSO on quality of life (QOL). One study examined 846 high-risk women of whom 44% underwent RRSO and 56% had periodic screening.[208] Of the 368 BRCA1/2 mutation carriers, 72% underwent RRSO. No significant differences were observed in QOL scores (as assessed by the Short Form-36) between those with RRSO or screening or compared with the general population; however, women with RRSO had fewer breast and ovarian cancer worries (P < .001), more favorable cancer risk perception (P < .05) but more endocrine symptoms (P < .001) and worse sexual functioning (P < .05). Of note, 37% of women used HRT following RRSO, although 62% were either perimenopausal or postmenopausal.[208] Researchers then examined 450 premenopausal high-risk women who had chosen either RRSO (36%) or screening (64%). Of those in the RRSO group, 47% used HRT. HRT users (n = 77) had fewer vasomotor symptoms than nonusers (n = 87) (P < 0.05), although more vasomotor symptoms than women in the screening group (n = 286). Likewise, women who underwent RRSO and used HRT had more sexual discomfort due to vaginal dryness and dyspareunia than those in the screening group (P < .01). Therefore, while such symptoms are improved via HRT use, HRT is not completely effective and additional work needs to be done.

The long-term nononcologic effects of RRSO in BRCA1/2 mutation carriers are unknown. In the general population, RRSO has been associated with increased cardiovascular disease, dementia, death from lung cancer, and overall mortality.[209,210,211,212,213] When age at oophorectomy has been analyzed, the most detrimental effect has been seen in women who undergo RRSO before age 45 and do not take estrogen-replacement therapy.[209]BRCA1/2 mutation carriers undergoing RRSO may have an increased risk of metabolic syndrome.[214] RRSO has also been associated with an improvement in short-term mortality in this population.[178] The benefits related to cancer risk reduction following RRSO are clear, but further data on the long-term nononcologic risks and benefits are needed.

References:

1. U.S. Preventive Services Task Force.: Genetic risk assessment and BRCA mutation testing for breast and ovarian cancer susceptibility: recommendation statement. Ann Intern Med 143 (5): 355-61, 2005.
2. American College of Medical Genetics.: Genetic susceptibility to breast and ovarian cancer: assessment, counseling and testing guidelines. New York: New York State Department of Health, American College of Medical Genetics Foundation, 1999. Also available online. Last accessed March 8, 2007.
3. National Comprehensive Cancer Network.: NCCN Clinical Practice Guidelines in Oncology: Genetic/Familial High-Risk Assessment: Breast and Ovarian. Version 1.2006. Rockledge, PA : National Comprehensive Cancer Network, 2006. Available online. Last accessed March 8, 2007.
4. American Society of Clinical Oncology.: American Society of Clinical Oncology policy statement update: genetic testing for cancer susceptibility. J Clin Oncol 21 (12): 2397-406, 2003.
5. ACOG committee opinion. Breast-ovarian cancer screening. Number 239, August 2000. American College of Obstetricians and Gynecologists. Committee on genetics. Int J Gynaecol Obstet 75 (3): 339-40, 2001.
6. Thomas DB, Gao DL, Self SG, et al.: Randomized trial of breast self-examination in Shanghai: methodology and preliminary results. J Natl Cancer Inst 89 (5): 355-65, 1997.
7. Scheuer L, Kauff N, Robson M, et al.: Outcome of preventive surgery and screening for breast and ovarian cancer in BRCA mutation carriers. J Clin Oncol 20 (5): 1260-8, 2002.
8. Brekelmans CT, Seynaeve C, Bartels CC, et al.: Effectiveness of breast cancer surveillance in BRCA1/2 gene mutation carriers and women with high familial risk. J Clin Oncol 19 (4): 924-30, 2001.
9. Burke W, Daly M, Garber J, et al.: Recommendations for follow-up care of individuals with an inherited predisposition to cancer. II. BRCA1 and BRCA2. Cancer Genetics Studies Consortium. JAMA 277 (12): 997-1003, 1997.
10. Shapiro S: Periodic screening for breast cancer: the Health Insurance Plan project and its sequelae, 1963-1986. Baltimore, Md: Johns Hopkins University Press, 1988.
11. Kerlikowske K, Grady D, Barclay J, et al.: Effect of age, breast density, and family history on the sensitivity of first screening mammography. JAMA 276 (1): 33-8, 1996.
12. Kerlikowske K, Carney PA, Geller B, et al.: Performance of screening mammography among women with and without a first-degree relative with breast cancer. Ann Intern Med 133 (11): 855-63, 2000.
13. Kerlikowske K, Grady D, Barclay J, et al.: Positive predictive value of screening mammography by age and family history of breast cancer. JAMA 270 (20): 2444-50, 1993.
14. Tilanus-Linthorst M, Verhoog L, Obdeijn IM, et al.: A BRCA1/2 mutation, high breast density and prominent pushing margins of a tumor independently contribute to a frequent false-negative mammography. Int J Cancer 102 (1): 91-5, 2002.
15. Tilanus-Linthorst MM, Kriege M, Boetes C, et al.: Hereditary breast cancer growth rates and its impact on screening policy. Eur J Cancer 41 (11): 1610-7, 2005.
16. Mitchell G, Antoniou AC, Warren R, et al.: Mammographic density and breast cancer risk in BRCA1 and BRCA2 mutation carriers. Cancer Res 66 (3): 1866-72, 2006.
17. Miller AB, To T, Baines CJ, et al.: Canadian National Breast Screening Study-2: 13-year results of a randomized trial in women aged 50-59 years. J Natl Cancer Inst 92 (18): 1490-9, 2000.
18. Sharan SK, Morimatsu M, Albrecht U, et al.: Embryonic lethality and radiation hypersensitivity mediated by Rad51 in mice lacking Brca2. Nature 386 (6627): 804-10, 1997.
19. Gowen LC, Avrutskaya AV, Latour AM, et al.: BRCA1 required for transcription-coupled repair of oxidative DNA damage. Science 281 (5379): 1009-12, 1998.
20. Abbott DW, Freeman ML, Holt JT: Double-strand break repair deficiency and radiation sensitivity in BRCA2 mutant cancer cells. J Natl Cancer Inst 90 (13): 978-85, 1998.
21. Andrieu N, Easton DF, Chang-Claude J, et al.: Effect of chest X-rays on the risk of breast cancer among BRCA1/2 mutation carriers in the international BRCA1/2 carrier cohort study: a report from the EMBRACE, GENEPSO, GEO-HEBON, and IBCCS Collaborators' Group. J Clin Oncol 24 (21): 3361-6, 2006.
22. Narod SA, Lubinski J, Ghadirian P, et al.: Screening mammography and risk of breast cancer in BRCA1 and BRCA2 mutation carriers: a case-control study. Lancet Oncol 7 (5): 402-6, 2006.
23. Goldfrank D, Chuai S, Bernstein JL, et al.: Effect of mammography on breast cancer risk in women with mutations in BRCA1 or BRCA2. Cancer Epidemiol Biomarkers Prev 15 (11): 2311-3, 2006.
24. Kuhl CK, Schrading S, Leutner CC, et al.: Surveillance of "high risk" women with proven or suspected familial (hereditary) breast cancer: First midterm results of a multi-modality clinical screening trial . [Abstract] Proceedings of the American Society of Clinical Oncology 22: A-4, 2, 2003..
25. Kriege M, Brekelmans CT, Boetes C, et al.: Efficacy of MRI and mammography for breast-cancer screening in women with a familial or genetic predisposition. N Engl J Med 351 (5): 427-37, 2004.
26. Lehman CD, Blume JD, Weatherall P, et al.: Screening women at high risk for breast cancer with mammography and magnetic resonance imaging. Cancer 103 (9): 1898-905, 2005.
27. Leach MO, Boggis CR, Dixon AK, et al.: Screening with magnetic resonance imaging and mammography of a UK population at high familial risk of breast cancer: a prospective multicentre cohort study (MARIBS). Lancet 365 (9473): 1769-78, 2005 May 21-27.
28. Warner E, Plewes DB, Hill KA, et al.: Surveillance of BRCA1 and BRCA2 mutation carriers with magnetic resonance imaging, ultrasound, mammography, and clinical breast examination. JAMA 292 (11): 1317-25, 2004.
29. Lehman CD, Isaacs C, Schnall MD, et al.: Cancer yield of mammography, MR, and US in high-risk women: prospective multi-institution breast cancer screening study. Radiology 244 (2): 381-8, 2007.
30. Sardanelli F, Podo F, D'Agnolo G, et al.: Multicenter comparative multimodality surveillance of women at genetic-familial high risk for breast cancer (HIBCRIT study): interim results. Radiology 242 (3): 698-715, 2007.
31. Lord SJ, Lei W, Craft P, et al.: A systematic review of the effectiveness of magnetic resonance imaging (MRI) as an addition to mammography and ultrasound in screening young women at high risk of breast cancer. Eur J Cancer 43 (13): 1905-17, 2007.
32. Saslow D, Boetes C, Burke W, et al.: American Cancer Society guidelines for breast screening with MRI as an adjunct to mammography. CA Cancer J Clin 57 (2): 75-89, 2007 Mar-Apr.
33. Kuhl CK, Schrading S, Leutner CC, et al.: Mammography, breast ultrasound, and magnetic resonance imaging for surveillance of women at high familial risk for breast cancer. J Clin Oncol 23 (33): 8469-76, 2005.
34. O'Driscoll D, Warren R, MacKay J, et al.: Screening with breast ultrasound in a population at moderate risk due to family history. J Med Screen 8 (2): 106-9, 2001.
35. Berg WA, Blume JD, Cormack JB, et al.: Combined screening with ultrasound and mammography vs mammography alone in women at elevated risk of breast cancer. JAMA 299 (18): 2151-63, 2008.
36. Shtern F: Digital mammography and related technologies: a perspective from the National Cancer Institute. Radiology 183 (3): 629-30, 1992.
37. Lewin JM, D'Orsi CJ, Hendrick RE, et al.: Clinical comparison of full-field digital mammography and screen-film mammography for detection of breast cancer. AJR Am J Roentgenol 179 (3): 671-7, 2002.
38. Pisano ED, Gatsonis C, Hendrick E, et al.: Diagnostic performance of digital versus film mammography for breast-cancer screening. N Engl J Med 353 (17): 1773-83, 2005.
39. Colditz GA, Rosner BA, Speizer FE: Risk factors for breast cancer according to family history of breast cancer. For the Nurses' Health Study Research Group. J Natl Cancer Inst 88 (6): 365-71, 1996.
40. Narod S, Lynch H, Conway T, et al.: Increasing incidence of breast cancer in family with BRCA1 mutation. Lancet 341 (8852): 1101-2, 1993.
41. Narod SA, Goldgar D, Cannon-Albright L, et al.: Risk modifiers in carriers of BRCA1 mutations. Int J Cancer 64 (6): 394-8, 1995.
42. McCredie M, Paul C, Skegg DC, et al.: Family history and risk of breast cancer in New Zealand. Int J Cancer 73 (4): 503-7, 1997.
43. Andrieu N, Goldgar DE, Easton DF, et al.: Pregnancies, breast-feeding, and breast cancer risk in the International BRCA1/2 Carrier Cohort Study (IBCCS). J Natl Cancer Inst 98 (8): 535-44, 2006.
44. Jernström H, Lerman C, Ghadirian P, et al.: Pregnancy and risk of early breast cancer in carriers of BRCA1 and BRCA2. Lancet 354 (9193): 1846-50, 1999.
45. Cullinane CA, Lubinski J, Neuhausen SL, et al.: Effect of pregnancy as a risk factor for breast cancer in BRCA1/BRCA2 mutation carriers. Int J Cancer 117 (6): 988-91, 2005.
46. Friedman E, Kotsopoulos J, Lubinski J, et al.: Spontaneous and therapeutic abortions and the risk of breast cancer among BRCA mutation carriers. Breast Cancer Res 8 (2): R15, 2006.
47. Collaborative Group on Hormonal Factors in Breast Cancer.: Breast cancer and breastfeeding: collaborative reanalysis of individual data from 47 epidemiological studies in 30 countries, including 50302 women with breast cancer and 96973 women without the disease. Lancet 360 (9328): 187-95, 2002.
48. Jernström H, Lubinski J, Lynch HT, et al.: Breast-feeding and the risk of breast cancer in BRCA1 and BRCA2 mutation carriers. J Natl Cancer Inst 96 (14): 1094-8, 2004.
49. Breast cancer and hormonal contraceptives: collaborative reanalysis of individual data on 53 297 women with breast cancer and 100 239 women without breast cancer from 54 epidemiological studies. Collaborative Group on Hormonal Factors in Breast Cancer. Lancet 347 (9017): 1713-27, 1996.
50. Ursin G, Henderson BE, Haile RW, et al.: Does oral contraceptive use increase the risk of breast cancer in women with BRCA1/BRCA2 mutations more than in other women? Cancer Res 57 (17): 3678-81, 1997.
51. Narod SA, Dubé MP, Klijn J, et al.: Oral contraceptives and the risk of breast cancer in BRCA1 and BRCA2 mutation carriers. J Natl Cancer Inst 94 (23): 1773-9, 2002.
52. Jernström H, Loman N, Johannsson OT, et al.: Impact of teenage oral contraceptive use in a population-based series of early-onset breast cancer cases who have undergone BRCA mutation testing. Eur J Cancer 41 (15): 2312-20, 2005.
53. Milne RL, Knight JA, John EM, et al.: Oral contraceptive use and risk of early-onset breast cancer in carriers and noncarriers of BRCA1 and BRCA2 mutations. Cancer Epidemiol Biomarkers Prev 14 (2): 350-6, 2005.
54. Olsson H, Jernström H, Alm P, et al.: Proliferation of the breast epithelium in relation to menstrual cycle phase, hormonal use, and reproductive factors. Breast Cancer Res Treat 40 (2): 187-96, 1996.
55. Narod SA, Risch H, Moslehi R, et al.: Oral contraceptives and the risk of hereditary ovarian cancer. Hereditary Ovarian Cancer Clinical Study Group. N Engl J Med 339 (7): 424-8, 1998.
56. Chen CL, Weiss NS, Newcomb P, et al.: Hormone replacement therapy in relation to breast cancer. JAMA 287 (6): 734-41, 2002.
57. Writing Group for the Women's Health Initiative Investigators.: Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results From the Women's Health Initiative randomized controlled trial. JAMA 288 (3): 321-33, 2002.
58. Chlebowski RT, Hendrix SL, Langer RD, et al.: Influence of estrogen plus progestin on breast cancer and mammography in healthy postmenopausal women: the Women's Health Initiative Randomized Trial. JAMA 289 (24): 3243-53, 2003.
59. Chlebowski RT, Kuller LH, Prentice RL, et al.: Breast cancer after use of estrogen plus progestin in postmenopausal women. N Engl J Med 360 (6): 573-87, 2009.
60. Schuurman AG, van den Brandt PA, Goldbohm RA: Exogenous hormone use and the risk of postmenopausal breast cancer: results from The Netherlands Cohort Study. Cancer Causes Control 6 (5): 416-24, 1995.
61. Steinberg KK, Thacker SB, Smith SJ, et al.: A meta-analysis of the effect of estrogen replacement therapy on the risk of breast cancer. JAMA 265 (15): 1985-90, 1991.
62. Colditz GA, Egan KM, Stampfer MJ: Hormone replacement therapy and risk of breast cancer: results from epidemiologic studies. Am J Obstet Gynecol 168 (5): 1473-80, 1993.
63. Sellers TA, Mink PJ, Cerhan JR, et al.: The role of hormone replacement therapy in the risk for breast cancer and total mortality in women with a family history of breast cancer. Ann Intern Med 127 (11): 973-80, 1997.
64. Stanford JL, Weiss NS, Voigt LF, et al.: Combined estrogen and progestin hormone replacement therapy in relation to risk of breast cancer in middle-aged women. JAMA 274 (2): 137-42, 1995.
65. Gorsky RD, Koplan JP, Peterson HB, et al.: Relative risks and benefits of long-term estrogen replacement therapy: a decision analysis. Obstet Gynecol 83 (2): 161-6, 1994.
66. Rebbeck TR, Friebel T, Wagner T, et al.: Effect of short-term hormone replacement therapy on breast cancer risk reduction after bilateral prophylactic oophorectomy in BRCA1 and BRCA2 mutation carriers: the PROSE Study Group. J Clin Oncol 23 (31): 7804-10, 2005.
67. Eisen A, Lubinski J, Gronwald J, et al.: Hormone therapy and the risk of breast cancer in BRCA1 mutation carriers. J Natl Cancer Inst 100 (19): 1361-7, 2008.
68. Chlebowski RT, Prentice RL: Menopausal hormone therapy in BRCA1 mutation carriers: uncertainty and caution. J Natl Cancer Inst 100 (19): 1341-3, 2008.
69. Fisher B, Costantino JP, Wickerham DL, et al.: Tamoxifen for prevention of breast cancer: report of the National Surgical Adjuvant Breast and Bowel Project P-1 Study. J Natl Cancer Inst 90 (18): 1371-88, 1998.
70. Veronesi U, Maisonneuve P, Costa A, et al.: Prevention of breast cancer with tamoxifen: preliminary findings from the Italian randomised trial among hysterectomised women. Italian Tamoxifen Prevention Study. Lancet 352 (9122): 93-7, 1998.
71. Powles T, Eeles R, Ashley S, et al.: Interim analysis of the incidence of breast cancer in the Royal Marsden Hospital tamoxifen randomised chemoprevention trial. Lancet 352 (9122): 98-101, 1998.
72. King MC, Wieand S, Hale K, et al.: Tamoxifen and breast cancer incidence among women with inherited mutations in BRCA1 and BRCA2: National Surgical Adjuvant Breast and Bowel Project (NSABP-P1) Breast Cancer Prevention Trial. JAMA 286 (18): 2251-6, 2001.
73. Narod SA, Brunet JS, Ghadirian P, et al.: Tamoxifen and risk of contralateral breast cancer in BRCA1 and BRCA2 mutation carriers: a case-control study. Hereditary Breast Cancer Clinical Study Group. Lancet 356 (9245): 1876-81, 2000.
74. Pierce LJ, Levin AM, Rebbeck TR, et al.: Ten-year multi-institutional results of breast-conserving surgery and radiotherapy in BRCA1/2-associated stage I/II breast cancer. J Clin Oncol 24 (16): 2437-43, 2006.
75. Gronwald J, Tung N, Foulkes WD, et al.: Tamoxifen and contralateral breast cancer in BRCA1 and BRCA2 carriers: an update. Int J Cancer 118 (9): 2281-4, 2006.
76. Vogel VG, Costantino JP, Wickerham DL, et al.: Effects of tamoxifen vs raloxifene on the risk of developing invasive breast cancer and other disease outcomes: the NSABP Study of Tamoxifen and Raloxifene (STAR) P-2 trial. JAMA 295 (23): 2727-41, 2006.
77. Land SR, Wickerham DL, Costantino JP, et al.: Patient-reported symptoms and quality of life during treatment with tamoxifen or raloxifene for breast cancer prevention: the NSABP Study of Tamoxifen and Raloxifene (STAR) P-2 trial. JAMA 295 (23): 2742-51, 2006.
78. Ariyan S: Prophylactic mastectomy for precancerous and high-risk lesions of the breast. Can J Surg 28 (3): 262-4, 266, 1985.
79. Hartmann LC, Schaid DJ, Woods JE, et al.: Efficacy of bilateral prophylactic mastectomy in women with a family history of breast cancer. N Engl J Med 340 (2): 77-84, 1999.
80. Hartmann LC, Sellers TA, Schaid DJ, et al.: Efficacy of bilateral prophylactic mastectomy in BRCA1 and BRCA2 gene mutation carriers. J Natl Cancer Inst 93 (21): 1633-7, 2001.
81. Meijers-Heijboer H, van Geel B, van Putten WL, et al.: Breast cancer after prophylactic bilateral mastectomy in women with a BRCA1 or BRCA2 mutation. N Engl J Med 345 (3): 159-64, 2001.
82. Rebbeck TR, Friebel T, Lynch HT, et al.: Bilateral prophylactic mastectomy reduces breast cancer risk in BRCA1 and BRCA2 mutation carriers: the PROSE Study Group. J Clin Oncol 22 (6): 1055-62, 2004.
83. van Sprundel TC, Schmidt MK, Rookus MA, et al.: Risk reduction of contralateral breast cancer and survival after contralateral prophylactic mastectomy in BRCA1 or BRCA2 mutation carriers. Br J Cancer 93 (3): 287-92, 2005.
84. Evans DG, Baildam AD, Anderson E, et al.: Risk reducing mastectomy: outcomes in 10 European centres. J Med Genet 46 (4): 254-8, 2009.
85. Kauff ND, Brogi E, Scheuer L, et al.: Epithelial lesions in prophylactic mastectomy specimens from women with BRCA mutations. Cancer 97 (7): 1601-8, 2003.
86. Hoogerbrugge N, Bult P, de Widt-Levert LM, et al.: High prevalence of premalignant lesions in prophylactically removed breasts from women at hereditary risk for breast cancer. J Clin Oncol 21 (1): 41-5, 2003.
87. Kroiss R, Winkler V, Kalteis K, et al.: Prevalence of pre-malignant and malignant lesions in prophylactic mastectomy specimens of BRCA1 mutation carriers: comparison with a control group. J Cancer Res Clin Oncol 134 (10): 1113-21, 2008.
88. Scott CI, Iorgulescu DG, Thorne HJ, et al.: Clinical, pathological and genetic features of women at high familial risk of breast cancer undergoing prophylactic mastectomy. Clin Genet 64 (2): 111-21, 2003.
89. Isern AE, Loman N, Malina J, et al.: Histopathological findings and follow-up after prophylactic mastectomy and immediate breast reconstruction in 100 women from families with hereditary breast cancer. Eur J Surg Oncol 34 (10): 1148-54, 2008.
90. Adem C, Reynolds C, Soderberg CL, et al.: Pathologic characteristics of breast parenchyma in patients with hereditary breast carcinoma, including BRCA1 and BRCA2 mutation carriers. Cancer 97 (1): 1-11, 2003.
91. Lerman C, Hughes C, Croyle RT, et al.: Prophylactic surgery decisions and surveillance practices one year following BRCA1/2 testing. Prev Med 31 (1): 75-80, 2000.
92. Stefanek ME, Helzlsouer KJ, Wilcox PM, et al.: Predictors of and satisfaction with bilateral prophylactic mastectomy. Prev Med 24 (4): 412-9, 1995.
93. Schrag D, Kuntz KM, Garber JE, et al.: Decision analysis--effects of prophylactic mastectomy and oophorectomy on life expectancy among women with BRCA1 or BRCA2 mutations. N Engl J Med 336 (20): 1465-71, 1997.
94. Unic I, Stalmeier PF, Verhoef LC, et al.: Assessment of the time-tradeoff values for prophylactic mastectomy of women with a suspected genetic predisposition to breast cancer. Med Decis Making 18 (3): 268-77, 1998 Jul-Sep.
95. Grann VR, Panageas KS, Whang W, et al.: Decision analysis of prophylactic mastectomy and oophorectomy in BRCA1-positive or BRCA2-positive patients. J Clin Oncol 16 (3): 979-85, 1998.
96. Meijers-Heijboer EJ, Verhoog LC, Brekelmans CT, et al.: Presymptomatic DNA testing and prophylactic surgery in families with a BRCA1 or BRCA2 mutation. Lancet 355 (9220): 2015-20, 2000.
97. Giuliano AE, Boolbol S, Degnim A, et al.: Society of Surgical Oncology: position statement on prophylactic mastectomy. Approved by the Society of Surgical Oncology Executive Council, March 2007. Ann Surg Oncol 14 (9): 2425-7, 2007.
98. Olson JE, Sellers TA, Iturria SJ, et al.: Bilateral oophorectomy and breast cancer risk reduction among women with a family history. Cancer Detect Prev 28 (5): 357-60, 2004.
99. Struewing JP, Watson P, Easton DF, et al.: Prophylactic oophorectomy in inherited breast/ovarian cancer families. J Natl Cancer Inst Monogr (17): 33-5, 1995.
100. Rebbeck TR, Levin AM, Eisen A, et al.: Breast cancer risk after bilateral prophylactic oophorectomy in BRCA1 mutation carriers. J Natl Cancer Inst 91 (17): 1475-9, 1999.
101. Rebbeck TR, Lynch HT, Neuhausen SL, et al.: Prophylactic oophorectomy in carriers of BRCA1 or BRCA2 mutations. N Engl J Med 346 (21): 1616-22, 2002.
102. Kauff ND, Satagopan JM, Robson ME, et al.: Risk-reducing salpingo-oophorectomy in women with a BRCA1 or BRCA2 mutation. N Engl J Med 346 (21): 1609-15, 2002.
103. Kauff ND, Domchek SM, Friebel TM, et al.: Risk-reducing salpingo-oophorectomy for the prevention of BRCA1- and BRCA2-associated breast and gynecologic cancer: a multicenter, prospective study. J Clin Oncol 26 (8): 1331-7, 2008.
104. Rebbeck TR, Kauff ND, Domchek SM: Meta-analysis of risk reduction estimates associated with risk-reducing salpingo-oophorectomy in BRCA1 or BRCA2 mutation carriers. J Natl Cancer Inst 101 (2): 80-7, 2009.
105. Chabner E, Nixon A, Gelman R, et al.: Family history and treatment outcome in young women after breast-conserving surgery and radiation therapy for early-stage breast cancer. J Clin Oncol 16 (6): 2045-51, 1998.
106. Leonard CE, Sedlacek S, Shapiro H, et al.: Lumpectomy and breast radiotherapy in breast cancer patients with a family history of breast cancer, ovarian cancer, or both. Breast J 8 (3): 154-61, 2002 May-Jun.
107. Freedman LM, Buchholz TA, Thames HD, et al.: Local-regional control in breast cancer patients with a possible genetic predisposition. Int J Radiat Oncol Biol Phys 48 (4): 951-7, 2000.
108. Harrold EV, Turner BC, Matloff ET, et al.: Local recurrence in the conservatively treated breast cancer patient: a correlation with age and family history. Cancer J Sci Am 4 (5): 302-7, 1998 Sep-Oct.
109. Haas JA, Schultz DJ, Peterson ME, et al.: An analysis of age and family history on outcome after breast-conservation treatment: the University of Pennsylvania experience. Cancer J Sci Am 4 (5): 308-15, 1998 Sep-Oct.
110. Robson ME, Chappuis PO, Satagopan J, et al.: A combined analysis of outcome following breast cancer: differences in survival based on BRCA1/BRCA2 mutation status and administration of adjuvant treatment. Breast Cancer Res 6 (1): R8-R17, 2004.
111. Robson M, Svahn T, McCormick B, et al.: Appropriateness of breast-conserving treatment of breast carcinoma in women with germline mutations in BRCA1 or BRCA2: a clinic-based series. Cancer 103 (1): 44-51, 2005.
112. Seynaeve C, Verhoog LC, van de Bosch LM, et al.: Ipsilateral breast tumour recurrence in hereditary breast cancer following breast-conserving therapy. Eur J Cancer 40 (8): 1150-8, 2004.
113. Metcalfe K, Lynch HT, Ghadirian P, et al.: Contralateral breast cancer in BRCA1 and BRCA2 mutation carriers. J Clin Oncol 22 (12): 2328-35, 2004.
114. Haffty BG, Harrold E, Khan AJ, et al.: Outcome of conservatively managed early-onset breast cancer by BRCA1/2 status. Lancet 359 (9316): 1471-7, 2002.
115. Vaidya JS, Baum M: Management of early-onset breast cancer and BRCA1 or BRCA2 status. Lancet 360 (9333): 640; author reply 640-1, 2002.
116. Alpert TE, Haffty BG: Conservative management of breast cancer in BRCA1/2 mutation carriers. Clin Breast Cancer 5 (1): 37-42, 2004.
117. Shen SX, Weaver Z, Xu X, et al.: A targeted disruption of the murine Brca1 gene causes gamma-irradiation hypersensitivity and genetic instability. Oncogene 17 (24): 3115-24, 1998.
118. Leong T, Whitty J, Keilar M, et al.: Mutation analysis of BRCA1 and BRCA2 cancer predisposition genes in radiation hypersensitive cancer patients. Int J Radiat Oncol Biol Phys 48 (4): 959-65, 2000.
119. Pierce LJ, Strawderman M, Narod SA, et al.: Effect of radiotherapy after breast-conserving treatment in women with breast cancer and germline BRCA1/2 mutations. J Clin Oncol 18 (19): 3360-9, 2000.
120. Shanley S, McReynolds K, Ardern-Jones A, et al.: Late toxicity is not increased in BRCA1/BRCA2 mutation carriers undergoing breast radiotherapy in the United Kingdom. Clin Cancer Res 12 (23): 7025-32, 2006.
121. Mullan PB, Quinn JE, Gilmore PM, et al.: BRCA1 and GADD45 mediated G2/M cell cycle arrest in response to antimicrotubule agents. Oncogene 20 (43): 6123-31, 2001.
122. Quinn JE, Kennedy RD, Mullan PB, et al.: BRCA1 functions as a differential modulator of chemotherapy-induced apoptosis. Cancer Res 63 (19): 6221-8, 2003.
123. Moynahan ME, Cui TY, Jasin M: Homology-directed dna repair, mitomycin-c resistance, and chromosome stability is restored with correction of a Brca1 mutation. Cancer Res 61 (12): 4842-50, 2001.
124. Husain A, He G, Venkatraman ES, et al.: BRCA1 up-regulation is associated with repair-mediated resistance to cis-diamminedichloroplatinum(II). Cancer Res 58 (6): 1120-3, 1998.
125. Lafarge S, Sylvain V, Ferrara M, et al.: Inhibition of BRCA1 leads to increased chemoresistance to microtubule-interfering agents, an effect that involves the JNK pathway. Oncogene 20 (45): 6597-606, 2001.
126. Sgagias MK, Wagner KU, Hamik B, et al.: Brca1-deficient murine mammary epithelial cells have increased sensitivity to CDDP and MMS. Cell Cycle 3 (11): 1451-6, 2004.
127. Bhattacharyya A, Ear US, Koller BH, et al.: The breast cancer susceptibility gene BRCA1 is required for subnuclear assembly of Rad51 and survival following treatment with the DNA cross-linking agent cisplatin. J Biol Chem 275 (31): 23899-903, 2000.
128. Deans AJ, Khanna KK, McNees CJ, et al.: Cyclin-dependent kinase 2 functions in normal DNA repair and is a therapeutic target in BRCA1-deficient cancers. Cancer Res 66 (16): 8219-26, 2006.
129. De Soto JA, Wang X, Tominaga Y, et al.: The inhibition and treatment of breast cancer with poly (ADP-ribose) polymerase (PARP-1) inhibitors. Int J Biol Sci 2 (4): 179-85, 2006.
130. Kennedy RD, Quinn JE, Mullan PB, et al.: The role of BRCA1 in the cellular response to chemotherapy. J Natl Cancer Inst 96 (22): 1659-68, 2004.
131. Hay T, Patrick T, Winton D, et al.: Brca2 deficiency in the murine small intestine sensitizes to p53-dependent apoptosis and leads to the spontaneous deletion of stem cells. Oncogene 24 (23): 3842-6, 2005.
132. Chappuis PO, Goffin J, Wong N, et al.: A significant response to neoadjuvant chemotherapy in BRCA1/2 related breast cancer. J Med Genet 39 (8): 608-10, 2002.
133. Byrski T, Huzarski T, Dent R, et al.: Response to neoadjuvant therapy with cisplatin in BRCA1-positive breast cancer patients. Breast Cancer Res Treat 115 (2): 359-63, 2009.
134. van Nagell JR Jr, DePriest PD, Ueland FR, et al.: Ovarian cancer screening with annual transvaginal sonography: findings of 25,000 women screened. Cancer 109 (9): 1887-96, 2007.
135. Hermsen BB, Olivier RI, Verheijen RH, et al.: No efficacy of annual gynaecological screening in BRCA1/2 mutation carriers; an observational follow-up study. Br J Cancer 96 (9): 1335-42, 2007.
136. Stirling D, Evans DG, Pichert G, et al.: Screening for familial ovarian cancer: failure of current protocols to detect ovarian cancer at an early stage according to the international Federation of gynecology and obstetrics system. J Clin Oncol 23 (24): 5588-96, 2005.
137. Olivier RI, Lubsen-Brandsma MA, Verhoef S, et al.: CA125 and transvaginal ultrasound monitoring in high-risk women cannot prevent the diagnosis of advanced ovarian cancer. Gynecol Oncol 100 (1): 20-6, 2006.
138. Meeuwissen PA, Seynaeve C, Brekelmans CT, et al.: Outcome of surveillance and prophylactic salpingo-oophorectomy in asymptomatic women at high risk for ovarian cancer. Gynecol Oncol 97 (2): 476-82, 2005.
139. Dørum A, Kristensen GB, Abeler VM, et al.: Early detection of familial ovarian cancer. Eur J Cancer 32A (10): 1645-51, 1996.
140. Tailor A, Bourne TH, Campbell S, et al.: Results from an ultrasound-based familial ovarian cancer screening clinic: a 10-year observational study. Ultrasound Obstet Gynecol 21 (4): 378-85, 2003.
141. Karlan BY, Raffel LJ, Crvenkovic G, et al.: A multidisciplinary approach to the early detection of ovarian carcinoma: rationale, protocol design, and early results. Am J Obstet Gynecol 169 (3): 494-501, 1993.
142. Muto MG, Cramer DW, Brown DL, et al.: Screening for ovarian cancer: the preliminary experience of a familial ovarian cancer center. Gynecol Oncol 51 (1): 12-20, 1993.
143. Liede A, Karlan BY, Baldwin RL, et al.: Cancer incidence in a population of Jewish women at risk of ovarian cancer. J Clin Oncol 20 (6): 1570-7, 2002.
144. Laframboise S, Nedelcu R, Murphy J, et al.: Use of CA-125 and ultrasound in high-risk women. Int J Gynecol Cancer 12 (1): 86-91, 2002 Jan-Feb.
145. Woodward ER, Sleightholme HV, Considine AM, et al.: Annual surveillance by CA125 and transvaginal ultrasound for ovarian cancer in both high-risk and population risk women is ineffective. BJOG 114 (12): 1500-9, 2007.
146. van der Velde NM, Mourits MJ, Arts HJ, et al.: Time to stop ovarian cancer screening in BRCA1/2 mutation carriers? Int J Cancer 124 (4): 919-23, 2009.
147. NIH consensus conference. Ovarian cancer. Screening, treatment, and follow-up. NIH Consensus Development Panel on Ovarian Cancer. JAMA 273 (6): 491-7, 1995.
148. Kramer BS, Gohagan J, Prorok PC, et al.: A National Cancer Institute sponsored screening trial for prostatic, lung, colorectal, and ovarian cancers. Cancer 71 (2 Suppl): 589-93, 1993.
149. Pepe MS, Etzioni R, Feng Z, et al.: Phases of biomarker development for early detection of cancer. J Natl Cancer Inst 93 (14): 1054-61, 2001.
150. Grosse SD, Khoury MJ: What is the clinical utility of genetic testing? Genet Med 8 (7): 448-50, 2006.
151. Finch A, Shaw P, Rosen B, et al.: Clinical and pathologic findings of prophylactic salpingo-oophorectomies in 159 BRCA1 and BRCA2 carriers. Gynecol Oncol 100 (1): 58-64, 2006.
152. Andersen MR, Goff BA, Lowe KA, et al.: Combining a symptoms index with CA 125 to improve detection of ovarian cancer. Cancer 113 (3): 484-9, 2008.
153. Skates SJ, Xu FJ, Yu YH, et al.: Toward an optimal algorithm for ovarian cancer screening with longitudinal tumor markers. Cancer 76 (10 Suppl): 2004-10, 1995.
154. Skates SJ, Menon U, MacDonald N, et al.: Calculation of the risk of ovarian cancer from serial CA-125 values for preclinical detection in postmenopausal women. J Clin Oncol 21 (10 Suppl): 206s-210s, 2003.
155. Menon U, Skates SJ, Lewis S, et al.: Prospective study using the risk of ovarian cancer algorithm to screen for ovarian cancer. J Clin Oncol 23 (31): 7919-26, 2005.
156. Greene MH, Piedmonte M, Alberts D, et al.: A prospective study of risk-reducing salpingo-oophorectomy and longitudinal CA-125 screening among women at increased genetic risk of ovarian cancer: design and baseline characteristics: a Gynecologic Oncology Group study. Cancer Epidemiol Biomarkers Prev 17 (3): 594-604, 2008.
157. Gagnon A, Ye B: Discovery and application of protein biomarkers for ovarian cancer. Curr Opin Obstet Gynecol 20 (1): 9-13, 2008.
158. Hennessy BT, Murph M, Nanjundan M, et al.: Ovarian cancer: linking genomics to new target discovery and molecular markers--the way ahead. Adv Exp Med Biol 617: 23-40, 2008.
159. Badgwell D, Bast RC Jr: Early detection of ovarian cancer. Dis Markers 23 (5-6): 397-410, 2007.
160. Petricoin EF, Ardekani AM, Hitt BA, et al.: Use of proteomic patterns in serum to identify ovarian cancer. Lancet 359 (9306): 572-7, 2002.
161. Zhang Z, Bast RC Jr, Yu Y, et al.: Three biomarkers identified from serum proteomic analysis for the detection of early stage ovarian cancer. Cancer Res 64 (16): 5882-90, 2004.
162. Koehn H, Oehler MK: Proteins' promise--progress and challenges in ovarian cancer proteomics. Menopause Int 13 (4): 148-53, 2007.
163. Visintin I, Feng Z, Longton G, et al.: Diagnostic markers for early detection of ovarian cancer. Clin Cancer Res 14 (4): 1065-72, 2008.
164. Simon R: Roadmap for developing and validating therapeutically relevant genomic classifiers. J Clin Oncol 23 (29): 7332-41, 2005.
165. Risch HA: Hormonal etiology of epithelial ovarian cancer, with a hypothesis concerning the role of androgens and progesterone. J Natl Cancer Inst 90 (23): 1774-86, 1998.
166. Hankinson SE, Colditz GA, Hunter DJ, et al.: A prospective study of reproductive factors and risk of epithelial ovarian cancer. Cancer 76 (2): 284-90, 1995.
167. Gronwald J, Byrski T, Huzarski T, et al.: Influence of selected lifestyle factors on breast and ovarian cancer risk in BRCA1 mutation carriers from Poland. Breast Cancer Res Treat 95 (2): 105-9, 2006.
168. Modan B, Hartge P, Hirsh-Yechezkel G, et al.: Parity, oral contraceptives, and the risk of ovarian cancer among carriers and noncarriers of a BRCA1 or BRCA2 mutation. N Engl J Med 345 (4): 235-40, 2001.
169. McLaughlin JR, Risch HA, Lubinski J, et al.: Reproductive risk factors for ovarian cancer in carriers of BRCA1 or BRCA2 mutations: a case-control study. Lancet Oncol 8 (1): 26-34, 2007.
170. Whittemore AS, Harris R, Itnyre J: Characteristics relating to ovarian cancer risk: collaborative analysis of 12 US case-control studies. IV. The pathogenesis of epithelial ovarian cancer. Collaborative Ovarian Cancer Group. Am J Epidemiol 136 (10): 1212-20, 1992.
171. Narod SA, Sun P, Ghadirian P, et al.: Tubal ligation and risk of ovarian cancer in carriers of BRCA1 or BRCA2 mutations: a case-control study. Lancet 357 (9267): 1467-70, 2001.
172. Rutter JL, Wacholder S, Chetrit A, et al.: Gynecologic surgeries and risk of ovarian cancer in women with BRCA1 and BRCA2 Ashkenazi founder mutations: an Israeli population-based case-control study. J Natl Cancer Inst 95 (14): 1072-8, 2003.
173. Miracle-McMahill HL, Calle EE, Kosinski AS, et al.: Tubal ligation and fatal ovarian cancer in a large prospective cohort study. Am J Epidemiol 145 (4): 349-57, 1997.
174. Collaborative Group on Epidemiological Studies of Ovarian Cancer, Beral V, Doll R, et al.: Ovarian cancer and oral contraceptives: collaborative reanalysis of data from 45 epidemiological studies including 23,257 women with ovarian cancer and 87,303 controls. Lancet 371 (9609): 303-14, 2008.
175. Whittemore AS, Balise RR, Pharoah PD, et al.: Oral contraceptive use and ovarian cancer risk among carriers of BRCA1 or BRCA2 mutations. Br J Cancer 91 (11): 1911-5, 2004.
176. McGuire V, Felberg A, Mills M, et al.: Relation of contraceptive and reproductive history to ovarian cancer risk in carriers and noncarriers of BRCA1 gene mutations. Am J Epidemiol 160 (7): 613-8, 2004.
177. Grabrick DM, Hartmann LC, Cerhan JR, et al.: Risk of breast cancer with oral contraceptive use in women with a family history of breast cancer. JAMA 284 (14): 1791-8, 2000.
178. Domchek SM, Friebel TM, Neuhausen SL, et al.: Mortality after bilateral salpingo-oophorectomy in BRCA1 and BRCA2 mutation carriers: a prospective cohort study. Lancet Oncol 7 (3): 223-9, 2006.
179. Leeper K, Garcia R, Swisher E, et al.: Pathologic findings in prophylactic oophorectomy specimens in high-risk women. Gynecol Oncol 87 (1): 52-6, 2002.
180. Olivier RI, van Beurden M, Lubsen MA, et al.: Clinical outcome of prophylactic oophorectomy in BRCA1/BRCA2 mutation carriers and events during follow-up. Br J Cancer 90 (8): 1492-7, 2004.
181. Colgan TJ, Murphy J, Cole DE, et al.: Occult carcinoma in prophylactic oophorectomy specimens: prevalence and association with BRCA germline mutation status. Am J Surg Pathol 25 (10): 1283-9, 2001.
182. Powell CB, Kenley E, Chen LM, et al.: Risk-reducing salpingo-oophorectomy in BRCA mutation carriers: role of serial sectioning in the detection of occult malignancy. J Clin Oncol 23 (1): 127-32, 2005.
183. Callahan MJ, Crum CP, Medeiros F, et al.: Primary fallopian tube malignancies in BRCA-positive women undergoing surgery for ovarian cancer risk reduction. J Clin Oncol 25 (25): 3985-90, 2007.
184. Piek JM, van Diest PJ, Zweemer RP, et al.: Dysplastic changes in prophylactically removed Fallopian tubes of women predisposed to developing ovarian cancer. J Pathol 195 (4): 451-6, 2001.
185. Paley PJ, Swisher EM, Garcia RL, et al.: Occult cancer of the fallopian tube in BRCA-1 germline mutation carriers at prophylactic oophorectomy: a case for recommending hysterectomy at surgical prophylaxis. Gynecol Oncol 80 (2): 176-80, 2001.
186. Rose PG, Shrigley R, Wiesner GL: Germline BRCA2 mutation in a patient with fallopian tube carcinoma: a case report. Gynecol Oncol 77 (2): 319-20, 2000.
187. Zweemer RP, van Diest PJ, Verheijen RH, et al.: Molecular evidence linking primary cancer of the fallopian tube to BRCA1 germline mutations. Gynecol Oncol 76 (1): 45-50, 2000.
188. Piek JM, Torrenga B, Hermsen B, et al.: Histopathological characteristics of BRCA1- and BRCA2-associated intraperitoneal cancer: a clinic-based study. Fam Cancer 2 (2): 73-8, 2003.
189. Levine DA, Argenta PA, Yee CJ, et al.: Fallopian tube and primary peritoneal carcinomas associated with BRCA mutations. J Clin Oncol 21 (22): 4222-7, 2003.
190. Aziz S, Kuperstein G, Rosen B, et al.: A genetic epidemiological study of carcinoma of the fallopian tube. Gynecol Oncol 80 (3): 341-5, 2001.
191. Kindelberger DW, Lee Y, Miron A, et al.: Intraepithelial carcinoma of the fimbria and pelvic serous carcinoma: Evidence for a causal relationship. Am J Surg Pathol 31 (2): 161-9, 2007.
192. Thompson D, Easton DF; Breast Cancer Linkage Consortium.: Cancer Incidence in BRCA1 mutation carriers. J Natl Cancer Inst 94 (18): 1358-65, 2002.
193. Lavie O, Hornreich G, Ben-Arie A, et al.: BRCA germline mutations in Jewish women with uterine serous papillary carcinoma. Gynecol Oncol 92 (2): 521-4, 2004.
194. Levine DA, Lin O, Barakat RR, et al.: Risk of endometrial carcinoma associated with BRCA mutation. Gynecol Oncol 80 (3): 395-8, 2001.
195. Goshen R, Chu W, Elit L, et al.: Is uterine papillary serous adenocarcinoma a manifestation of the hereditary breast-ovarian cancer syndrome? Gynecol Oncol 79 (3): 477-81, 2000.
196. Beiner ME, Finch A, Rosen B, et al.: The risk of endometrial cancer in women with BRCA1 and BRCA2 mutations. A prospective study. Gynecol Oncol 104 (1): 7-10, 2007.
197. Chen KT, Schooley JL, Flam MS: Peritoneal carcinomatosis after prophylactic oophorectomy in familial ovarian cancer syndrome. Obstet Gynecol 66 (3 Suppl): 93S-94S, 1985.
198. Lynch HT, Bewtra C, Lynch JF: Familial ovarian carcinoma. Clinical nuances. Am J Med 81 (6): 1073-6, 1986.
199. Lynch HT, Watson P, Bewtra C, et al.: Hereditary ovarian cancer. Heterogeneity in age at diagnosis. Cancer 67 (5): 1460-6, 1991.
200. Tobacman JK, Greene MH, Tucker MA, et al.: Intra-abdominal carcinomatosis after prophylactic oophorectomy in ovarian-cancer-prone families. Lancet 2 (8302): 795-7, 1982.
201. Truong LD, Maccato ML, Awalt H, et al.: Serous surface carcinoma of the peritoneum: a clinicopathologic study of 22 cases. Hum Pathol 21 (1): 99-110, 1990.
202. Piver MS, Jishi MF, Tsukada Y, et al.: Primary peritoneal carcinoma after prophylactic oophorectomy in women with a family history of ovarian cancer. A report of the Gilda Radner Familial Ovarian Cancer Registry. Cancer 71 (9): 2751-5, 1993.
203. Casey MJ, Synder C, Bewtra C, et al.: Intra-abdominal carcinomatosis after prophylactic oophorectomy in women of hereditary breast ovarian cancer syndrome kindreds associated with BRCA1 and BRCA2 mutations. Gynecol Oncol 97 (2): 457-67, 2005.
204. Finch A, Beiner M, Lubinski J, et al.: Salpingo-oophorectomy and the risk of ovarian, fallopian tube, and peritoneal cancers in women with a BRCA1 or BRCA2 Mutation. JAMA 296 (2): 185-92, 2006.
205. Chen S, Iversen ES, Friebel T, et al.: Characterization of BRCA1 and BRCA2 mutations in a large United States sample. J Clin Oncol 24 (6): 863-71, 2006.
206. Antoniou A, Pharoah PD, Narod S, et al.: Average risks of breast and ovarian cancer associated with BRCA1 or BRCA2 mutations detected in case Series unselected for family history: a combined analysis of 22 studies. Am J Hum Genet 72 (5): 1117-30, 2003.
207. Risch HA, McLaughlin JR, Cole DE, et al.: Population BRCA1 and BRCA2 mutation frequencies and cancer penetrances: a kin-cohort study in Ontario, Canada. J Natl Cancer Inst 98 (23): 1694-706, 2006.
208. Madalinska JB, Hollenstein J, Bleiker E, et al.: Quality-of-life effects of prophylactic salpingo-oophorectomy versus gynecologic screening among women at increased risk of hereditary ovarian cancer. J Clin Oncol 23 (28): 6890-8, 2005.
209. Rocca WA, Grossardt BR, de Andrade M, et al.: Survival patterns after oophorectomy in premenopausal women: a population-based cohort study. Lancet Oncol 7 (10): 821-8, 2006.
210. Rocca WA, Bower JH, Maraganore DM, et al.: Increased risk of parkinsonism in women who underwent oophorectomy before menopause. Neurology 70 (3): 200-9, 2008.
211. Shuster LT, Rhodes DJ, Gostout BS, et al.: Premature menopause or early menopause: Long-term health consequences. Maturitas : , 2009.
212. Parker WH, Broder MS, Chang E, et al.: Ovarian conservation at the time of hysterectomy and long-term health outcomes in the nurses' health study. Obstet Gynecol 113 (5): 1027-37, 2009.
213. Rivera CM, Grossardt BR, Rhodes DJ, et al.: Increased cardiovascular mortality after early bilateral oophorectomy. Menopause 16 (1): 15-23, 2009 Jan-Feb.
214. Michelsen TM, Pripp AH, Tonstad S, et al.: Metabolic syndrome after risk-reducing salpingo-oophorectomy in women at high risk for hereditary breast ovarian cancer: a controlled observational study. Eur J Cancer 45 (1): 82-9, 2009.

Psychosocial Issues in Inherited Breast Cancer Syndromes

Introduction

Psychosocial research in the context of cancer genetic testing helps to define psychological outcomes, interpersonal and familial effects, and cultural and community responses. It also identifies behavioral factors that encourage or impede surveillance and other health behaviors. It can enhance decision-making about risk-reduction interventions, evaluate psychosocial interventions to reduce distress and/or other negative sequelae related to risk notification and genetic testing, provide data to help resolve ethical concerns, and predict the interest in testing of various groups.

Research in these areas is limited by few randomized controlled trials, and many reports are based on uncontrolled studies of selected high-risk populations. Research is likely to expand considerably with access to larger populations of at-risk individuals.

There have been a number of descriptions of cancer genetics programs that provide genetic susceptibility testing.[1,2,3,4,5,6,7,8,9] The development of such programs was encouraged by federal funding of multidisciplinary research programs that offered intensive genetic counseling for hereditary cancer syndromes, psychological assessment and back-up, and physician involvement.[10]

Interest in and Uptake of Genetic Testing

Decisions about whether to pursue breast cancer genetic testing involve complex biologic, behavioral and social elements.[11] There are vast differences in interest in and actual uptake rates of testing reported in the literature. In a systematic review of 40 peer-reviewed primary clinical studies published between 1990 and May 2002,[12] it was reported that sampling frame and other methodological variables contributed to the wide variability. On average, interest in genetic testing was 66% (range 20%–96%), while actual uptake of genetic testing was 59% (range 25%–96%) (odds ratio [OR] 1.27; 95% confidence interval [CI], 1.16–1.39). In multivariate analysis, personal and family history of cancer, study recruitment and setting were all associated with testing uptake. Researchers in Ontario, Canada, surveyed 416 women diagnosed with epithelial ovarian cancer or fallopian tube cancer between 2002 and 2004. Although genetic testing is freely available in Canada to women diagnosed with ovarian cancer or fallopian tube cancer, only 80 of 416 women surveyed (19%) had undergone clinical genetic testing. The researchers concluded that uptake of genetic testing may rise with increased public awareness directed at both physicians and patients.[13]

Furthermore, accrual statistics in different populations are difficult to compare because there are many points in the genetic risk assessment process at which a family member can decline, and no standard method of reporting these rates has been developed.[14] Factors that may influence uptake of testing include:

  • Cost of genetic testing.
  • How informative testing would be (e.g., presence of a known mutation in the family or ethnic group vs. lack of an identified mutation).
  • Extent to which genetic test results are likely to influence clinical decision-making.[15]

Motivations for testing include the belief that testing positive would increase one's motivation to get regular clinical breast examinations, to do breast self-exams, and to get recommended mammograms.[16] Women known to be at increased risk do not necessarily adhere to screening recommendations at higher rates than women at population risk, nor do they necessarily pursue or complete genetic testing, though the data on this subject are contradictory.[17,18,19] An additional motivation for testing is to receive information that would benefit other family members.[20] Another motivator for testing may be recommendation by a physician. In a retrospective study of 335 women considering genetic testing, 77% reported that they wanted the opinion of the genetics physician about whether they should be tested, and 49% wanted the opinion of their primary care provider.[21]

In one study of women who pursued BRCA1 and BRCA2 mutation testing and received uninformative test results, 45% (17/40) were interested in undergoing additional testing for five large rearrangements (deletions and insertions) in the BRCA1 gene. There were no significant differences in BRCAPRO scores, age at time of genetic testing, number of children, or number of siblings between individuals who chose to pursue additional testing and those who declined. Women who chose to undergo additional testing were significantly less likely to have a diagnosis of breast or ovarian cancer at the time of initial testing.[22]

Limited data are available about the characteristics of at-risk individuals who decline to be or have never been tested. It is difficult to access samples of test decliners since they are people who also may be reluctant to participate in research studies. Studies of testing are difficult to compare because people may decline at different points and with different amounts of pretest education and counseling. One study found that 43% of affected and unaffected individuals from hereditary breast/ovarian cancer families completing a baseline interview regarding testing declined. Most individuals declining testing chose not to participate in educational sessions. Decliners were more likely to be male and unmarried and had fewer relatives affected with breast cancer. Those decliners who had high levels of cancer-related stress had higher levels of depression. Decliners lost to follow-up were significantly more likely to be affected with cancer.[23] Another study looked at a small number (n = 13) of women decliners who carry a 25% to 50% probability of harboring a BRCA mutation and found that these nontested women were more likely to be childless and have a higher educational level. This study showed that most women had decided not to undergo the test after serious deliberation about the risks and benefits. Satisfaction with frequent surveillance was given as one reason for nontesting in most of these women.[24] Other reasons for declining included having no children and becoming acquainted with breast/ovarian cancer in the family relatively early in their lives.[23,24] A third study evaluated characteristics of 34 individuals who declined BRCA1/2 testing in a large multicenter study in the United Kingdom. Decliners were younger compared with a national sample of test acceptors, and female decliners had lower mean scores on a measure of cancer worry. Although 78% of test decliners/deferrers felt that their health was at risk, they reported that learning about their BRCA1/2 mutation status would cause them to worry about the following:

  • Their children's health (76%).
  • Their life insurance (60%).
  • Their own health (56%).
  • Loss of their job (5%).
  • Receiving less screening if they did not carry a BRCA1/2 mutation (62%).

Apprehension about the impact of the test result was a more important factor in the reason to decline than concrete burdens such as time to travel to a genetics clinic and time away from work, family, and social obligations.[25] In 15% (n = 31) of individuals from 13 hereditary breast and ovarian cancer families who underwent genetic education and counseling and declined testing for a documented mutation in the family, positive changes in family relationships were reported, specifically greater expressiveness and cohesion, compared with those who pursued testing.[26]

Participation in breast cancer risk counseling among relatives of breast cancer patients is positively associated with higher levels of education, income, and positive health behaviors (nonsmokers, any current alcohol use, recent clinical breast exam), and perceived and objective risk perception.[27,28] Other predictors of participation are being married, having a family history of cancer, presence of a daughter, fear of stigma, and believing there are more reasons to be tested than not to be tested.[29]

Women recruited from high-risk clinics who have expressed their concern about breast cancer by seeking specialized medical attention are more likely than women recruited from registry sources to attend counseling and educational sessions about cancer genetics and genetic testing.[17,30] Genetic testing uptake was influenced by eligibility for free testing, history of breast or ovarian cancer, and Ashkenazi Jewish heritage.[15] Interest in testing declines sharply if it is not immediately available.[17] Knowledge about the details of cancer genetic testing is not associated with the decision to be tested,[31] suggesting a need for improved education about cancer genetics. Several studies suggest that interest in cancer genetic testing is generally high despite respondents' relative lack of knowledge regarding the pros and cons of attempting to learn one's mutation status.[28] One U.K. study suggested that proactive approaches to offering predictive testing (telephone calls and home visits) may be useful in increasing testing uptake among at-risk men.[32]

There are limited data on uptake of genetic counseling and testing among nonwhite populations, and further research will be needed to define factors influencing uptake in these populations.[30] In a study of African-American women at increased risk of breast cancer, those with a personal history of cancer or a greater perceived risk for developing cancer were more likely to report greater limitations or drawbacks of genetic testing. Those with more fatalistic beliefs about cancer, higher perceived risk of having a BRCA1/2 mutation, and more relatives affected with breast or ovarian cancer were more likely to consider undergoing BRCA1/2 testing.[33] In a case-control study of women who had been seen in a university-based primary care system, African-American women with a family history of breast or ovarian cancer were less likely to undergo BRCA1/2 testing compared with white women who had similar histories. Other predictors of testing used in that study include younger age, higher anxiety, belief that testing will provide reassurance, absence of concern about discrimination, and having had a primary care doctor or gynecologist discuss genetic testing with the patient.[34]

What People Bring to Genetic Testing: Impact of Risk Perception, Health Beliefs, and Personality Characteristics

The emerging literature in this area suggests that risk perceptions, health beliefs, psychological status, and personality characteristics are important factors in decision-making about breast/ovarian cancer genetic testing. Many women presenting at academic centers for BRCA1/2 testing arrive with a strong belief that they have a mutation, having decided they want genetic testing, but possessing little information about the risks or limitations of testing.[35] Most mean scores of psychological functioning at baseline for subjects in genetic counseling studies were within normal limits.[36] Nonetheless, a subset of subjects in many genetic counseling studies present with elevated anxiety, depression, or cancer worry.[37,38] Identification of these individuals is essential to prevent adverse outcomes.

A general tendency to overestimate inherited risk of breast and ovarian cancer has been noted in at-risk populations,[39,40,41] in cancer patients,[40,42,43] in spouses of breast and ovarian cancer patients,[44] and among women in the general population,[45,46,47] but underestimation of breast cancer risk in higher-risk and average-risk women also has been reported.[48] This overestimation may encourage a belief that BRCA1/2 genetic testing will be more informative than it is currently thought to be. There is some evidence that even counseling does not dissuade women at low to moderate risk from the belief that BRCA1 testing could be valuable.[30] Overestimation of both breast and ovarian cancer risk has been associated with nonadherence to physician-recommended screening practices.[49,50] A meta-analysis of 12 studies of outcomes of genetic counseling for breast/ovarian cancer showed that counseling improved the accuracy of risk perception.[51]

Women appear to be the prime communicators within families about the family history of breast cancer.[52] Higher numbers of maternal versus paternal transmission cases are reported,[53] likely due to family communication patterns, to the misconception that breast cancer risk can only be transmitted through the mother, and to the greater difficulty in recognizing paternal family histories because of the need to identify more distant relatives with cancer. Physicians and counselors taking a family history are encouraged to elicit paternal as well as maternal family histories of breast, ovarian, or other associated cancers.[52]

The accuracy of reported family history of breast or ovarian cancer varies; some studies found levels of accuracy above 90%,[54,55] with others finding more errors in the reporting of cancer in second-degree or more distant relatives [56] or in age of onset of cancer.[57] Less accuracy has been found in the reporting of cancers other than breast cancer. Ovarian cancer history was reported with 60% accuracy in one study compared with 83% accuracy in breast cancer history.[58] Providers should be aware that there are a few published cases of Munchausen syndrome in reporting of false family breast cancer history.[59] Much more common is erroneous reporting of family cancer history due to unintentional errors or gaps in knowledge, related in some cases to the early death of potential maternal informants about cancer family history.[52] (Refer to the Taking a Family History section of the Cancer Genetics Risk Assessment and Counseling summary.)

Targeted written,[60,61] video, CD-ROM, interactive computer program,[62,63,64,65,66] and culturally targeted educational materials [67] may be an effective and efficient means of increasing knowledge about the pros and cons of genetic testing. Such supplemental materials may allow more efficient use of the time allotted for pretest education and counseling by genetics and primary care providers and may discourage ineligible individuals from seeking genetic testing.[60]

Genetic Counseling for Hereditary Predisposition to Breast Cancer

Counseling for breast cancer risk typically involves individuals with family histories that are potentially attributable to BRCA1 or BRCA2. It also, however, may include individuals with family histories of Li-Fraumeni Syndrome, ataxia-telangiectasia, Cowden syndrome, or Peutz-Jeghers syndrome.[68] (See the Major Genes section of this summary.)

Management strategies for carriers may involve decisions about the nature, frequency, and timing of screening and surveillance procedures, chemoprevention, risk-reducing surgery, and use of hormone replacement therapy. The utilization of breast conservation and radiation as cancer therapy for women who are carriers may be influenced by knowledge of mutation status. (See the Interventions section of this summary.)

Counseling also includes consideration of related psychosocial concerns and discussion of planned family communication and the responsibility to warn other family members about the possibility of having an increased risk of breast, ovarian, and other cancers. Data are emerging that individual responses to being tested as adults are influenced by the results status of other family members.[69,70] Management of anxiety and distress are important not only as quality-of-life factors, but also because high anxiety may interfere with the understanding and integration of complex genetic and medical information as well as adherence to screening.[18,19,71] The limited number of medical interventions with proven benefit to mutation carriers provides further basis for the expectation that mutation carriers may experience increased anxiety, depression, and continuing uncertainty following disclosure of genetic test results.[72] Formal, objective evaluation of these outcomes are now emerging. (Refer to the sections below on Emotional Outcomes and Behavioral Outcomes.)

Published descriptions of counseling programs for BRCA1 (and subsequently for BRCA2) testing include strategies for gathering a family history, assessing eligibility for testing, communicating the considerable volume of relevant information about breast/ovarian cancer genetics and associated medical and psychosocial risks and benefits, and discussion of specialized ethical considerations about confidentiality and family communication.[3,73,74,75,76,77,78,79] Participant distress, intrusive thoughts about cancer, coping style, and social support were assessed in many prospective testing candidates. The psychosocial outcomes evaluated in these programs have included changes in knowledge about the genetics of breast/ovarian cancer after counseling, risk comprehension, psychological adjustment, family and social functioning, and reproductive and health behaviors.[80] A Dutch study of communication processes and satisfaction levels of counselees going through cancer genetic counseling for inherited cancer syndromes indicated that asking more medical questions (by the counselor), providing more psychosocial information, and longer eye contact by the counselor were associated with lower satisfaction levels. The provision of medical information by the counselor was most highly related to satisfaction and perception that needs have been fulfilled.[81] Additional research is needed on how to adequately address the emotional needs and feelings of control of counselees.

Many of the psychosocial outcome studies involve specialized, highly selected research populations, some of which were utilized to map and clone BRCA1 and BRCA2. One such example is K2082, an extensively studied kindred of more than 800 members of a Utah Mormon family in which a BRCA1 mutation accounts for the observed increased rates of breast and ovarian cancer. A study of the understanding that members of this kindred have about breast/ovarian cancer genetics found that, even in breast cancer research populations, there was incomplete knowledge about associated risks of colon and prostate cancer, the existence of options for risk-reducing mastectomy (RRM) and risk-reducing salpingo-oophorectomy (RRSO), and the complexity of existing psychosocial risks.[3] A meta-analysis of 21 studies found that genetic counseling was effective in increasing knowledge and improved the accuracy of perceived risk. Genetic counseling did not have a statistically significant long-term impact on affective outcomes including anxiety, distress, or cancer-specific worry and the behavioral outcome of cancer surveillance activities.[36] These prospective studies, however, were characterized by a heterogeneity of measures of cancer-specific worry and inconsistent findings in effects of change from baseline.[36]

It is not yet clearly established to what extent findings derived from special research populations, at least some of which have long awaited genetic testing for breast/ovarian cancer risk, are generalizable to other populations. For example, there are data to suggest that the BRCA1/2penetrance estimates derived from these dramatically affected families are substantial overestimates and do not apply to most families presenting for counseling and possible testing.[82]

Emotional Outcomes of Individuals

The few studies conducted to date of psychological outcomes associated with genetic testing for mutations in breast/ovarian cancer predisposition genes have shown low levels of distress among those found to be carriers and even lower levels among noncarriers.[60,83,84,85,86] A systematic review found that the studies assessing measures of distress (9 of 11 studies) found no change, or a decrease, in those parameters (including anxiety, depression, general distress, and situation distress) in people who had undergone testing at assessments done at 1 month or less, and 3 to 6 months later.[87] One follow-up study from the United Kingdom measured levels of cancer-related worry, general mental health, risk perception, intrusive or avoidant thoughts, and risk-management behaviors at baseline and 1, 4, and 12 months after results were provided. This study included 202 unaffected women and 59 unaffected men, of whom 91 tested positive and 170 tested negative. Results showed that while female noncarriers had significant (P <.001) reductions in cancer-related worry, female carriers younger than 50 years had an increase in cancer-related worry 1 month posttesting. These levels returned to baseline by 12 months but remained higher than noncarrier levels throughout the 12-month period. Female carriers engaged in more posttest screening than noncarriers (92% vs. 30%) within 12 months of test results disclosure. Thirty carriers had RRM and/or RRSO within the same time period.[88] A slightly smaller subset of this cohort was assessed again for cancer-related worry, general mental health and risk-management behaviors at 3 years post-genetic test result disclosure. One hundred fifty-four women and 39 males, including 71 carriers and 122 noncarriers, returned the questionnaire. The level of distress and cancer worry was similar between carriers and noncarriers. Female carriers had higher distress levels at 3 years versus 1 year post-disclosure, but their level of cancer worry decreased significantly over the same time period. In female noncarriers, although the level of cancer worry had decreased from baseline to 1 year post-disclosure, these levels returned to baseline by 3 years.[89] The authors did not comment on contextual factors that might influence distress and cancer worry levels. Another study reported that, compared with pretest levels, mean scores on 1-year posttest measures of cancer-specific distress and state-anxiety decreased significantly among noncarriers, while scores on these measures as well as on a measure of general distress, did not change among BRCA1/2 carriers.[90] One long-term study of 65 female participants explored the psychosocial consequences of carrying a BRCA1/2 mutation 5 years after genetic testing. Carriers did not differ from noncarriers on several distress measures. Although both groups showed significant increases in depression and anxiety compared with 1 year postdisclosure, these scores remained within normal limits for the general population.[91] Caution is advised by authors of these studies in interpretation of the results as they are all from programs in which results disclosure was preceded by extensive genetic counseling about risks and benefits of BRCA1/2 testing, psychological assessment, and in some cases exclusion of a few individuals who appeared highly distressed.[3] Intrusive thoughts (measured by the Impact of Event Scale [IES]) [92] about cancer diminished after results disclosure for both mutation-positive and mutation-negative individuals in one Dutch study.[93]

A prospective Australian study evaluated the psychological impact of genetic testing at baseline, 7 to 10 days, 4 months, and 12 months in 60 women of Ashkenazi Jewish heritage (ten with breast cancer, 50 unaffected). Of the 43 women who opted to learn their test results, 97% felt pleased to have had the test and, at 12 months of follow-up, none regretted having been tested. Seventeen women opted not to receive their results and had significantly lower levels of breast cancer anxiety than did those who opted to receive their results. Women with no history of cancer who opted to learn their results showed a progressive decrease in breast cancer anxiety over the 12-month study period compared with baseline measures. There was also no statistically significant difference in measures of depression and generalized anxiety from baseline to the follow-up assessments.[94] However, these results must be interpreted in light of the fact that only 7 of 43 women had deleterious mutations.

Despite generally positive findings regarding diminished distress in tested individuals, most studies also report increased distress among small subsets of tested individuals. Most, but not all, of these increases are within the normal range of distress. Increased distress has been noted by individuals receiving both positive and negative test results. Studies suggest that the psychological impact of an individual test result is highly influenced by the test result status of other family members. A 1999 study found that an individual's response to learning his or her own BRCA1/2 test result was significantly influenced by his or her gender and by the genetic test result status of other family members. Adverse, immediate outcomes were experienced by male carriers who were the first tested in their family or by noncarrier men whose siblings were all positive. In addition, female carriers who were the first in their families to be tested or whose siblings were all negative had significantly higher distress than other female carriers.[69] Another study found that spousal anxiety about genetic testing and supportiveness differentiated the impact of BRCA1/2 test results. When the spouse was highly anxious and unsupportive in style, the mutation carrier had significantly higher levels of distress. These studies illustrate that genetic test results are not received in a vacuum, and that researchers need to consider the context of the tested individual in determining which individuals applying for genetic testing may require additional emotional support.[70]

In another study, depression rates postdisclosure were unchanged for mutation carriers and markedly decreased for noncarriers.[23] An analysis of the distress of individuals receiving BRCA1 results in the context of their siblings' results, however, revealed patterns of response suggesting that certain subgroups of tested individuals have markedly increased levels of distress after disclosure that were not apparent when the analysis focused only on comparing the mean scores for carriers versus noncarriers.[69] Early optimistic findings may not sufficiently reflect the true complexity of response to disclosure of BRCA1/2 test results. Female carriers who had no carrier siblings had distress scores (IES) similar to those found in cancer patients 10 weeks after their diagnosis. The distress of male subjects was highly correlated with the status of their siblings' test results or lack thereof.[69] One pilot study suggested that women diagnosed more recently were more distressed after counseling.[95] A survey of women enrolled in a high-risk clinic found that heightened levels of distress may be more related to living with the awareness of a familial risk for cancer than with the genetic testing process itself. Obtaining genetic testing may be less stressful than living with the awareness of familial risk for cancer.[96] (For more detailed information about depression and anxiety associated with a cancer diagnosis, refer to the PDQ Supportive Care summaries on Anxiety Disorder; Depression; and Normal Adjustment and Distress.) Case descriptions have supported the importance of family relationships and test outcomes in shaping the distress of tested individuals.[97,98]

Although there are not yet reports of large-scale studies of the reactions of affected individuals to genetic testing, there are indications from several smaller studies that affected individuals who undergo genetic counseling and testing experience more distress than had been expected by professionals [99,100] and are less able themselves to anticipate the intensity of their reactions following result disclosure.[101] Female mutation carriers who have had breast cancer are often surprised by their high level of risk for ovarian cancer. Women mutation carriers who have had breast cancer worried more than unaffected women about developing ovarian cancer, though, in general, worry about ovarian cancer risk was found to be unrealistically low.[100] In addition, some distress related to the burden of conveying genetic information to relatives has been noted among those who are the first in their families to be tested.[99,102]

Several studies have compared the provision of breast cancer genetics services by different providers and the psychological impact on women at high and low risk for cancer. In a study of 735 women at all levels of risk for hereditary breast/ovarian cancer, the services of a multidisciplinary team of genetics specialists was compared with services provided by surgeons. There were no significant differences between groups in anxiety, cancer worry, or perceived risk.[103] In a Scottish study of 373 participants, an alternative model of cancer genetics services using genetics nurse specialists in community-based services was compared with standard genetics regional services. There was no difference in cancer worry or change in health behaviors between the two groups. Cancer worry decreased for both groups over a 6-month period. Women who dropped out of the study tended to be in the nurse provider arm or were at low risk of breast cancer.[104] In a small U.S. study, an evaluation of nurses and genetic counselors as providers of education about breast cancer susceptibility testing was conducted to compare outcomes of pretest education about breast cancer susceptibility. Four genetic counselors and two nurses completed specialized training in cancer genetics. Women receiving pretest education from nurses were as satisfied with information received and had equal degrees of perceived autonomy and partnership. The study findings suggest that with proper training and supervision, both genetic counselors and nurses can be effective in providing pretest education to women considering genetic susceptibility testing for breast cancer risk.[105]

There has been little empirical research in the communication of risk assessments to individuals at risk of breast/ovarian cancer syndromes. When asked to choose a preferred method, individuals undergoing genetic counseling for breast and ovarian cancer appear to prefer quantitative to qualitative presentation of risk information.[106,107] One study indicated that most women wanted information given both ways.[42] Information about the risk of developing breast cancer among women with a family history of breast cancer may be more accurately recalled when presented as odds ratios rather than in other forms.[108]

There is a small but growing body of literature on the use of decision aids as an adjunct to standard genetic counseling to assist patients in making informed decisions about genetic testing. One study measured the effectiveness of a decision aid for BRCA1/2 genetic testing given to women at the end of their first genetic counseling consultation. At 1 week and 6 months follow-up, the decision aid had no effect on informed choice, post-decisional regret or actual genetic testing decision. However, women who received the decision aid had significantly higher knowledge levels and felt more informed about genetic testing than women who received the control pamphlet. The decision aid also helped those women who did not have their blood drawn for genetic testing at the first visit to clarify their values about their testing decision.[109]

Preferences for delivery of breast cancer genetic testing are reported in one study [107] to include counseling conducted by a genetic counselor (42%) or oncologist (22%) rather than by a primary care physician (6%), nurse (12%), or gynecologist (5%). Patients in that study preferred results disclosure by an oncologist. Younger women especially expressed a need for individual consideration of their personal values and goals or potential emotional reactions to testing; 67% believed emotional support and counseling were a necessary part of posttest counseling. Most women (82%) wanted to be able to self-refer for genetic testing, without a physician referral.

Family Effects

Family communication about genetic testing and hereditary risk

Family communication about genetic testing for cancer susceptibility, and specifically about the results of BRCA1/2 genetic testing, is complex; there are few systematic data available on this topic. Gender appears to be an important variable in family communication and psychological outcomes. One study documented that female carriers are more likely to disclose their status to other family members (especially sisters and children aged 14–18 years) than are male carriers.[110] Among males, noncarriers were more likely than carriers to tell their sisters and children the results of their tests. BRCA1/2 carriers who disclosed their results to sisters had a slight decrease in psychological distress, compared with a slight increase in distress for carriers who chose not to tell their sisters. Findings from other studies suggest that there may be more communication about inherited breast and ovarian cancer risk among female family members than between female and male relatives (e.g., between brothers and sisters and/or mothers and sons).[52,111] One study found that men reported greater difficulty disclosing mutation-positive results to family members in comparison to women (90% vs. 70%).[112]

Family communication of BRCA1/2 test results to relatives is another factor affecting participation in testing. There have been more studies of communication with first-degree relatives and second-degree relatives than with more distant family members. One study investigated the process and content of communication among sisters about BRCA1/2 test results.[113] Study results suggest that both mutation carriers and women with uninformative results communicate with sisters to provide them with genetic risk information. Among relatives with whom genetic test results were not discussed, the most important reason given was that the affected women were not close to their relatives. Studies found that women with a BRCA mutation more often shared their results with their mother and adult sisters and daughters than with their father and adult brothers and sons.[114,115,116] A study that evaluated communication of test results to first-degree relatives at 4 months postdisclosure found that women aged 40 years or older were more likely to inform their parents of test results compared with younger women. Participants also were more likely to inform brothers of their results if the BRCA mutation was inherited through the paternal line.[115] Another study found that disclosure was limited mainly to first-degree relatives, and dissemination of information to distant relatives was problematic.[117] Age was a significant factor in informing distant relatives with younger patients being more willing to communicate their genetic test result.[113,114,117]

A few in-depth qualitative studies have looked at issues associated with family communication about genetic testing. Although the findings from these studies may not be generalizable to the larger population of at-risk persons, they illustrate the complexity of issues involved in conveying hereditary cancer risk information in families.[118] On the basis of 15 interviews conducted with women attending a familial cancer genetics clinic, the authors concluded that while women felt a sense of duty to discuss genetic testing with their relatives, they also experienced conflicting feelings of uncertainty, respect, and isolation. Decisions on whom in the family to inform and how to inform them about hereditary cancer and genetic testing may be influenced by tensions between women's need to fulfill social roles and their responsibilities toward themselves and others.[118] Another qualitative study of 21 women who attended a familial breast and ovarian cancer genetics clinic suggested that some women may find it difficult to communicate about inherited cancer risk with their partners and with certain relatives, especially brothers, because of those persons' own fears and worries about cancer.[111] This study also suggested that how genetic risk information is shared within families may depend on the existing norms for communicating about cancer in general. For example, family members may be generally open to sharing information about cancer with each other, may selectively avoid discussing cancer information with certain family members to protect themselves or other relatives from negative emotional reactions, or may ask a specific relative to act as an intermediary to disclosure of information to other family members.[119] The potential importance of persons outside the family, such as friends, as both confidantes about inherited cancer risk information and as sources of support for coping with this information was also noted in the study.[111]

A study of 31 mothers with a documented BRCA mutation explored patterns of dissemination to children.[120] Of those who chose to disclose test results to their children, age of offspring was the most important factor. Fifty percent of the children who were told were between ages 20 years and 29 years and slightly more than 25% of the children were aged 19 years or younger. Sons and daughters were notified in equal numbers. More than 70% of mothers informed their children within a week of learning their test result. Ninety-three percent of mothers who chose not to share their results with their children indicated that it was because their children were too young. These findings were consistent with three other studies showing that children younger than 13 years were less likely to be informed about test results compared with older children.[115,121,122] Another study of 187 mothers undergoing BRCA1/2 testing evaluated their need for resources to prepare for a facilitated conversation about sharing their BRCA1/2 testing results with their children. Seventy-eight percent of mothers were interested in three or more resources, including literature (93%), family counseling (86%), talk to prior participants (79%), and support groups (54%).[121]

A longitudinal study of 153 women self-referred for genetic testing for BRCA1 and BRCA2 mutations and 118 of their partners evaluated communication about genetic testing and distress before testing and at 6 months posttesting.[123] The study found that most couples discussed the decision to undergo testing (98%), most test participants felt their partners were supportive, and most women disclosed test results to their partners (97%, n = 148). Test participants who felt their partners were supportive during pretest discussions experienced less distress after disclosure, and partners who felt more comfortable sharing concerns with test participants pretest experienced less distress after disclosure. Six-month follow-up revealed that 22% of participants felt the need to talk about the testing experience with their partners in the week before the interview. Most participants (72%, n = 107) reported comfort in sharing concerns with their partners, and 5% (n = 7) reported relationship strain as a result of genetic testing. In couples in which the woman had a positive genetic test result, more relationship strain, more protective buffering of their partners, and more discussion of related concerns were reported than in couples in which the woman had a true-negative or uninformative result.[123]

There is a small but growing body of literature regarding psychological effects in men who have a family history of breast cancer and who are considering or have had BRCA testing. A qualitative study of 22 men from 16 high-risk families in Ireland revealed that more men in the study with daughters were tested than men without daughters. These men reported little communication with relatives about the illness, with some men reporting being excluded from discussion about cancer among female family members. Some men in the study also reported actively avoiding open discussion with daughters and other relatives.[124] In contrast, a study of 59 men testing positive for a BRCA1/2 mutation found that most men participated in family discussions about breast and/or ovarian cancer. However, fewer than half of the men participated in family discussions about risk-reducing surgery. The main reason given for having BRCA testing was concern for their children and a need for certainty about whether they could have transmitted the mutation to their children. In this study, 79% of participating men had at least one daughter. Most of these men described how their relationships had been strengthened after receipt of BRCA results, helping communication in the family and greater understanding.[125] Men in both studies expressed fears of developing cancer themselves. Irish men especially reported fear of cancer in sexual organs.

Family functioning

In a study of 212 individuals from 13 hereditary breast and ovarian cancer families who received genetic counseling and were offered BRCA1/2 testing for documented mutation in the family, individuals who were not tested were found 6 to 9 months later to have significantly greater increases in expressiveness and cohesiveness compared with those who were tested. Persons who were randomized to a client-centered versus problem-solving genetic counseling intervention had a significantly greater reduction in conflict, regardless of the test decision.[26]

Partners of high-risk women

Many studies have looked at the psychological effects in women of having a high risk of developing cancer, either on the basis of carrying a BRCA1/2 mutation or having a strong family history of cancer. However, few studies have looked at the effects on the partners of such women.

A Canadian study assessed 59 spouses of women found to have a BRCA1/2 mutation. All were supportive of their spouses' decision to undergo genetic testing and 17% wished they had been more involved in the genetic testing process. Spouses who reported that genetic testing had no impact on their relationship had long-term relationships (mean duration 27 years). Forty-six percent of spouses reported that their major concern was of their partner dying of cancer. Nineteen percent were concerned their spouse would develop cancer and 14% were concerned their children would also be BRCA1/2 mutation carriers.[126]

In a U.S. study, 118 partners of women undergoing genetic testing for mutations in BRCA1 and BRCA2 completed a survey prior to testing and then again 6 months following result disclosure. At 6 months, only 10 partners reported that they had not been told of the test result. Ninety-one percent reported that the testing had not caused strain on their relationship. Partners who were comfortable sharing concerns prior to testing experienced less distress following testing. Protective buffering was not found to impact distress levels of partners.[123]

An Australian study of 95 unaffected women at high risk of developing breast and/or ovarian cancer (13 mutation carriers and 82 with unknown mutation status) and their partners showed that although the majority of male partners had distress levels comparable to a normative population sample, 10% had significant levels of distress that indicated the need for further clinical intervention. Men with a high monitoring coping style and greater perceived breast cancer risk for their wife reported higher levels of distress. Open communication between the men and their partners and the occurrence of a cancer-related event in the wife's family in the last year were associated with lower distress levels. When men were asked what kind of information and support they would like for themselves and their partners, 57.9% reported that they would like more information about breast and ovarian cancer, and 32.6% said they would like more support in dealing with their partner's risk. Twenty-five percent of men had suggestions on how to improve services for partners of high-risk women, including strategies on how to best support their partner, greater encouragement from healthcare professionals to attend appointments, and meeting with other partners.[127]

At-risk males

A review of the literature on the experiences of males in BRCA1 and BRCA2 mutation–positive families reported that while the data are limited, men from mutation-positive families are less likely than females to participate in communication regarding genetics at every level, including the counseling and testing process. Men are less likely to be informed of genetic test results received by female relatives, and most men from these families do not pursue their own genetic testing.[128]

A study of Dutch men at increased risk of having inherited a BRCA1 mutation reported a tendency for the men to deny or minimize the emotional effects of their risk status, and to focus on medical implications for their female relatives. Men in these families, however, also reported considerable distress in relation to their female relatives.[129] In another study of male psychological functioning during breast cancer testing, 28 men belonging to 18 different high-risk families (with a 25% or 50% risk of having inherited a BRCA1/2 mutation) participated. The study purpose was to analyze distress in males at risk of carrying a BRCA1/2 mutation who applied for genetic testing. Of the men studied, most had low pretest distress; scores were lowest for men who were optimistic or who did not have daughters. Most mutation carriers had normal levels of anxiety and depression and reported no guilt, though some anticipated increased distress and feelings of responsibility if their daughters developed breast or ovarian cancer. None of the noncarriers reported feeling guilty.[130] In one study,[125] adherence to recommended screening guidelines after testing was analyzed. In this study, more than half of male carriers of mutations did not adhere to the screening guidelines recommended after disclosure of genetic test results. These findings are consistent with those for female carriers of BRCA1/2 mutations.[125,131]

A multicenter U.K. cohort study examined prospective outcomes of BRCA1/2 testing in 193 individuals, of which 20% were men aged 28 to 86 years. Men's distress levels were low, did not differ among carriers and noncarriers, and did not change from baseline (pre-genetic testing) to the 3-year follow-up. Twenty-two percent of male mutation carriers received colorectal cancer screening and 44% received prostate cancer screening;[89] however, it is unclear whether men in this study were following age-appropriate screening guidelines.

Children

Several studies have explored communication of BRCA test results to at-risk children. Across all studies, the rate of disclosure to children ranging in age from 4 to 25 years is approximately 50%.[114,115,117,121,132,133,134,135] In general, age of offspring was the most important factor in deciding whether to disclose test results. In one study of 31 mothers disclosing their BRCA test results, 50% of the children who were informed of the results were aged 20 to 29 years and slightly more than 25% of the children were aged 19 years or younger. Sons and daughters were notified in equal numbers.[120] Similarly, in another study of 42 female BRCA mutation carriers, 83% of offspring older than age 18 years were told of the results, while only 21% of offspring aged 13 years or younger were told.[121]

Several studies have also looked at the timing of disclosure to children after parents receive their test results. Although the majority of children were told within a week to several months after results disclosure,[115,120,121] some parents chose to delay disclosure.[121] Reasons for delaying disclosure included waiting for the child to get older, allowing time for the parent to adjust to the information, and waiting until results could be shared in person (in the case of adult children living away from home).[121]

One study looked at the reaction of children to results disclosure or the effect on the parent-child relationship of communicating the results.[121] With regard to offspring's understanding of the information, almost half of parents from one study reported that their child did not appear to understand the significance of a positive test result, although older children were reported to have a better understanding. This same study also showed that 48% of parents reported at least one negative reaction in their child, ranging from anxiety or concern (22%) to crying and fear (26%). It should be noted, however, that in this study children's level of understanding and reactions to the test result were measured qualitatively and based only on the parents' perception. Also, given the retrospective design of the study, there was a potential for recall bias. There were no significant differences in emotional reaction depending on age or gender of the child. Lastly, 65% of parents reported no change in their relationship with their child, while 5 parents (22%) reported a strengthening of their relationship.

Another study of 187 mothers undergoing BRCA1/2 testing evaluated their need for resources to prepare for a facilitated conversation about sharing their BRCA1/2 testing results with their children. Seventy-eight percent of mothers were interested in three or more resources, including literature (93%), family counseling (86%), talking to prior participants (79%), and support groups (54%).[136]

Testing for BRCA1/2 has been almost universally limited to adults older than 18 years. The risks of testing children for adult-onset disorders (such as breast and ovarian cancer), as inferred from developmental data on children's medical understanding and ability to provide informed consent, have been outlined in several reports.[137,138,139,140] Surveys of parental interest in testing children for adult-onset hereditary cancers suggest that parents are more eager to test their children than to be tested themselves for a breast cancer gene, suggesting potential conflicts for providers.[141,142] In a general population survey in the United States, 71% of parents said that it was moderately, very, or extremely likely that if they carried a breast-cancer predisposing mutation, they would test a 13-year-old daughter now to determine her breast cancer gene status.[141] To date, no data exist on the testing of children for BRCA1/2, though some researchers believe it is necessary to test the validity of assumptions underlying the general prohibition of testing of children for breast/ovarian cancer and other adult-onset disease genes.[143,144,145] In one study, 20 children (aged 11 to 17 years) of a selected group of mothers undergoing genetic testing (80% of whom previously had breast cancer and all of whom had discussed BRCA1/2 testing with their children) completed self-report questionnaires on their health beliefs and attitudes toward cancer, feelings related to cancer, and behavioral problems.[146] Ninety percent of children thought they would want cancer risk information as adults; half worried about themselves or a family member developing cancer. There was no evidence of emotional distress or behavioral problems. Another study by this group [134] found that 1 month after disclosure of BRCA1/2 genetic test results, 53% of 42 enrolled mothers of children aged 8 to 17 years had discussed their result with one or more of their children. Age of the child rather than mutation status of the mother influenced whether they were told, as did family health communication style.

In one study, participants who told children younger than 13 years about their carrier status had increased distress, and those who did not tell their young children experienced a slight decrease in distress. Communication with young children was found to be influenced by developmental variables such as age and style of parent/child communication.[134]

Reproductive issues

Prenatal diagnosis of breast/ovarian cancer predisposition is generally discouraged.[147] Adult age at onset, good prognosis for many breast cancer patients, and the expectation of greater medical progress by the time disease onset might be expected decades into the future make the prospect of prenatal diagnosis an uncomfortable one for many geneticists, leading potentially to charges of eugenics.[141,148] Limited data on the use of this technology are available. In a small series, 26 mutation carriers indicated that pregnancy termination based on mutation status would not be acceptable. Interestingly, a small percentage of nonmutation carriers felt that termination of a pregnancy, where the fetus was a mutation carrier was acceptable.[149] In another study of 213 women with a known BRCA1 or BRCA2 mutation, while many participants expressed extreme concern over the possibility of passing on the mutation to an offspring, only 13% of the women said they would consider preimplantation diagnosis or other assisted reproductive technologies.[150] Historically, in Huntington disease, the uptake of prenatal diagnosis and termination is low.[151,152]

The U.K. Human Fertilization and Embryology authority has approved the use of preimplantation genetic diagnosis (PGD) for hereditary breast and ovarian cancer. In a sample of 102 women with a BRCA mutation, most were supportive of PGD but only 38% of the women who had completed their families would consider it for themselves and only 14% of women who were contemplating a future pregnancy would consider it.[153]

Cultural/Community Effects

The recognition that BRCA1/2 mutations are prevalent, not only in breast/ovarian cancer families but also in some ethnic groups,[154] has led to considerable discussion of the ethical, psychological, and other implications of having one's ethnicity be a factor in determination of disease predisposition. Fears of genetic reductionism and the creation of a genetic underclass [155] have been voiced. Questions about the impact on the group of being singled out as having genetic vulnerability to breast cancer have been raised. There is also confusion about who gives or withholds permission for the group to be involved in studies of their genetic identity. These issues challenge traditional views on informed consent as a function of individual autonomy.[156]

A growing literature on the unique factors influencing a variety of cultural subgroups suggests the importance of developing culturally specific genetic counseling and educational approaches.[67,157,158,159,160]

Ethical Concerns

The human implications of the ethical issues raised by the advent of genetic testing for breast/ovarian cancer susceptibility are described in case studies,[161] essays,[72,162] and research reports. Issues about rights and responsibilities in families concerning the spread of information about genetic risk promise to be major ethical and legal dilemmas in the coming decades.

Studies have shown that 62% of studied family members were aware of the family history, and that 88% of hereditary breast/ovarian cancer family members surveyed have significant concerns about privacy and confidentiality. Expressed concern about cancer in third-degree relatives, or relatives farther removed, was about the same as that for first- or second-degree relatives of the proband.[163] Only half of surveyed first-degree relatives of women with breast or ovarian cancer felt that written permission should be required to disclose BRCA1/2 test results to a spouse or immediate family member. Attitudes toward testing varied by ethnicity, previous exposure to genetic information, age, optimism, and information style. Altruism is a factor motivating genetic testing in some people.[17] Many professional groups have made recommendations regarding informed consent.[17,28,76,164,165] There is some evidence that not all practitioners are aware of or follow these guidelines.[16] Research shows that many BRCA1/2 genetic testing consent forms do not fulfill recommendations by professional groups about the 11 areas that should be addressed,[164] and they omit highly relevant points of information.[16] In a study of women with a history of breast or ovarian cancer, the interviews yielded that the women reported feeling inadequately prepared for the ethical dilemmas they encountered when imparting genetic information to family members.[166] These data suggest that more preparation about disclosure to family members before testing reduces the emotional burden of disseminating genetic information to family members. Patients and health care providers would benefit from enhanced consideration of the ethical issues of warning family members about hereditary cancer risk. (For further information associated with ethics of cancer genetics and genetic testing, please refer to the PDQ summaries Cancer Genetics Risk Assessment and Counseling and the Cancer Genetics Overview Genetics.)

Psychosocial Aspects of Cancer Risk Management for Hereditary Breast and Ovarian Cancer

Decision aids for persons considering risk management options for hereditary breast and ovarian cancer

There is a small but growing body of literature on the use of decision aids as an adjunct to standard genetic counseling to assist patients in making informed decisions about cancer risk management. One study showed that the use of a decision aid consisting of individualized value assessment and cancer risk management information after receiving positive BRCA1/2 test results was associated with fewer intrusive thoughts and lower levels of depression at the 6-month follow-up in unaffected women. Use of the decision aid did not alter cancer risk management intentions and behaviors. Slightly detrimental effects on well-being and several decision-related outcomes, however, were noted among affected women.[167] Another study compared responses to a tailored decision aid (including a values-clarification exercise) versus a general information pamphlet intended for women making decisions about ovarian cancer risk management. In the short term, the women receiving the tailored decision aid showed a decrease in decisional conflict and increased knowledge compared with women receiving the pamphlet, but no differences in decisional outcomes were found between the two groups. In addition, the decision aid did not appear to alter the participant's baseline cancer risk management decisions.[168] A third decision aid focused on breast cancer risk management decision support for women with a BRCA1/2 mutation. Pre-evaluations and postevaluations of the decision aid in 20 women showed that use of the aid resulted in a significant decrease in decisional conflict, improvement in knowledge, and a decrease in uncertainty about tamoxifen use, RRM and RRSO. No significant differences were identified in cancer-related distress following the use of the tool.[169]

Uptake of cancer-risk management options

An increasing number of studies have examined uptake and adherence to cancer risk management options among individuals who have undergone genetic counseling and testing for BRCA1 and BRCA2 gene mutations. Findings from these studies are reported in Tables 8 and 9. Outcomes vary across studies and include uptake or adherence to screening (mammography, magnetic resonance imaging [MRI], CA 125, transvaginal ultrasound) as well as selection of RRM and RRSO. Studies generally report outcomes by mutation carrier or testing status (e.g., mutation-positive, mutation-negative, or declined genetic testing). Follow-up time after notification of genetic risk status also varied across studies, ranging from 12 months up to several years.

Findings from these studies suggest that breast screening often improves after notification of BRCA1/BRCA2 mutation carrier status; nonetheless, screening remains suboptimal. Fewer studies have examined adoption of MRI as a screening modality, probably due to the recent availability of efficacy data. Screening for ovarian cancer varied widely across studies, and also varied based on type of screening test (i.e., CA 125 serum testing vs. transvaginal ultrasound (TVUS) screening). However, ovarian cancer screening does not appear to be widely adopted by BRCA1/BRCA2 mutation carriers. Uptake of RRM varied widely across studies, and may be influenced by personal factors (such as younger age or having a family history of breast cancer), psychosocial factors (such as a desire for reduction of cancer-related distress), recommendations of the health care provider, and cultural or health care system factors. An individual's choice to have a bilateral mastectomy also appears to be influenced by pre-treatment genetic education and counseling regardless of the genetic test results.[170] Similarly, uptake of RRSO also varied across studies, and may be influenced by similar factors, including older age, personal history of breast cancer, perceived risk for ovarian cancer, cultural factors (i.e., country), and the recommendations of the health care provider.

Table 8. Uptake of RRM and/or Breast Screening (Mammography and/or Breast MRI) Among BRCA1 and BRCA2 Mutation Carriers

a Medical records as data source.
b Self-report as data source.
c Data source not specified.
MRI = magnetic resonance imaging.
Study Citation Study Population RRM Breast Screening Mammography and/or Breast MRI Length of Follow-up Comments
UNITED STATES
[171] Carriers (N = 237)a Carriers 23% Not applicable Mean 3.7 y Women opting for RRM were < age 60, had a prior diagnosis of breast cancer, and also underwent RRSO.
Median time to RRM; 124 days from receiving results.
[172] Carriers (N = 22)b Carriers 54% Not applicable 12 mo All participants had newly diagnosed breast cancer.
Noncarriers (N = 127)b Noncarriers 25%
[173] Carriers (N = 194)a, b Carriers 14.9% MAMMOGRAPHY Mean 24.8 mo; range 1.6–66.0 mo Women opting for RRM were younger and had more family members with breast or ovarian cancer.
Carriers 93.4%
MRI
Not evaluated
[174] Carriers (N = 37)b Carriers 0% MAMMOGRAPHY 24 mo  
Carriers 57%
Noncarriers 49%
Noncarriers (N = 92)b Noncarriers 0% Declined test 20%
Declined testing (N = 15)b   MRI
Not evaluated
[131] Carriers (N = 84)b Carriers 3% MAMMOGRAPHY 12 mo Screening adherence in carriers was unchanged from baseline.
Carriers 68%
Noncarriers (N = 83)b Noncarriers 0% Noncarriers 44%
Declined test 54%
Declined testing (N = 49)b   MRI
Not evaluated
INTERNATIONAL
[175] Carriers (N = 70)b Carriers 11% MAMMOGRAPHY 3 y  
Carriers 89%
MRI
Not evaluated
[176] Carriers (N = 34)b Carriers 9% MAMMOGRAPHY 12 mo  
Carriers 95%
Noncarriers 60%
Noncarriers (N = 34)b   MRI
Not evaluated
[177] Carriers (N = 26)b Carriers 54% Not applicable 12 mo Carriers opting for RRM had higher levels of general and cancer-related distress.
Noncarriers (N = 37)b Noncarriers 0%
[178] Carriers (N = 68)a Carriers 51% Carriers 49% Median 21 mo; range 10–61 mo Carriers opting for RRM tended to be younger.
Data based on specific method(s) not reported.
[179] Carriers (N = 517)b Carriers 30% (unaffected) Not applicable Not provided Women with a sister with breast cancer were more likely to have an RRM.
249 participants had a personal history of breast cancer.
[180] Carriers (N = 2,677)b Carriers 18% (unaffected) MAMMOGRAPHY 3.9 y; range 1.5–10.3 y Large differences in uptake of risk management options by country.
Carriers 87%
MRI
Carriers 31%
[181] Carriers (N = 537)c Carriers 21% Not Applicable Minimum 6 mo; median 36 mo  

Table 9. Uptake of RRSO and/or Gynecologic Screening Among BRCA1 and BRCA2 Mutation Carriers

a Medical records as data source.
b Self-report as data source.
c Data source not specified.
TVUS = transvaginal ultrasound.
Study Citation Study Population RRSO Gynecological Screening Length of Follow-up Comments
UNITED STATES
[171] (N = 240)a Carriers 51% Not applicable Mean 3.7 y Women opting for RRSO were < age 60, had a prior diagnosis of breast cancer, and also underwent RRM.
Median time to RRSO; 123 days from receiving results.
[182] Carriers (N = 132)b BRCA1 BRCA1 Not provided Specific method(s) of gynecological screening not reported.
Carriers 33% Carriers 53%
Noncarriers (N = 410)b BRCA2 BRCA2
Carriers 41% Carriers 50%
Noncarriers 8% Noncarriers 76%
[183] Carriers (N = 79)b Carriers 27% CA 125 12 mo  
Carriers 43%
Noncarriers 9%
Noncarriers (N = 44)b   Uninformative 27%
TVUS
Uninformative (N = 166)b   Carriers 40%
Noncarriers 21%
Uninformative 29%
[181] Carriers (N = 26)b Carriers 46% CA 125 24 mo  
Carriers 37%
Noncarriers 5%
Noncarriers (N = 66)b   Declined test 8%
TVUS
Declined testing (N = 12)b   Carriers 11%
Noncarriers 2%
Declined test 8%
[180] Carriers (N = 179)a, b Carriers 50.3% CA 125 Mean 24.8 mo; range 1.6–66.0 mo Women undergoing RRSO were older and more likely to have a personal history of breast cancer.
Carriers 67.6%
TVUS
Carriers 72.9%
[131] Carriers (N = 39)b Carriers 13% CA 125 12 mo  
Carriers 21%
TVUS
Carriers 15%
INTERNATIONAL
[172] Carriers (N = 70)b Carriers 29% CA 125 3 y  
Carriers 0%
TVUS
Carriers 67%
[173] Carriers aged =35 years (N = 16)b Carriers aged =35 years 75% CA 125 12 mo Women undergoing RRSO were older and had higher ovarian cancer risk perception.
Not evaluated
Carriers aged <35 years (N = 12)b Carriers aged <35 years 8% TVUS
Carriers aged =35 years 100%
Carriers aged < 35 years 30%
[174] Carriers (N = 26)b Carriers 50% NA 12 mo  
Noncarriers (N = 37)b
[175] Carriers (N = 45)a Carriers 64% Carriers 36% Median 24 mo; range 11–61 mo 83% of RRSOs were performed within 9 months of receiving test results.
Specific method(s) of gynecological screening not reported.
[184] Carriers (N = 160)a, b Carriers 64% Carriers 26% 12 mo Women undergoing RRSO had lower education levels, viewed ovarian cancer as incurable and believed strongly in the benefits of RRSO.
Specific method(s) of gynecological screening not reported.
[177] Carriers (N = 2,677)b Carriers 57% NA 3.9 y; range 1.5–10.3 y Large differences in uptake of risk management options by country.
[178] Carriers (N = 537)c Carriers 55% NA Minimum 6 mo; median 36 mo RRSO greatest in parous women aged >40 years.

On the other hand, many women found to be mutation carriers express interest in RRM in hopes of minimizing their risk of breast cancer. In one study of a number of unaffected women with no previous risk-reducing surgery who received results of BRCA1 testing following genetic counseling, 17% of carriers (2/12) intended to have mastectomies and 33% (4/12) intended to have oophorectomies.[83] In a later study of the same population, RRM was considered an important option by 35% of women who tested positive, whereas risk-reducing oophorectomy was considered an important option by 76%. A prospective study assessed the stability of risk management preferences over five time points (pre-BRCA testing to 9 months after results disclosure) among 80 Dutch women with a documented BRCA mutation. Forty-six participants indicated a preference for screening at baseline. Of 25 women who preferred RRM at baseline, 22 indicated the same preference 9 months after test results disclosure; however, it was not reported how many women actually had RRM.[185]

Initial interest does not always translate into the decision for surgery. Two different studies found low rates of RRM among mutation carriers in the year following result disclosure, one showing 3% (1 of 29) of carriers and the other 9% (3 of 34) of carriers having had this surgery.[131,173] Among members from a large BRCA1 kindred, utilization of cancer screening and/or risk-reducing surgeries was assessed at baseline (before disclosure of results), and at 1 year and 2 years after disclosure of BRCA1 test results. Of the 269 men and women who participated, complete data were obtained on 37 female carriers and 92 female noncarriers, all aged 25 years or older. At 2 years after disclosure of test results, none of the women had undergone RRM, although 4 of the 37 carriers (10.8%) said they were considering the procedure. In contrast, of the 26 women who had not had an oophorectomy prior to baseline, 46% (12 of 26) had obtained an oophorectomy by 2 years after testing. Of those carriers aged 25 to 39 years, 29% (5 of 17) underwent oophorectomy, while 78% (7 of 9) of the carriers aged 40 years and older had this procedure.[181] In a study assessing uptake of risk-reducing surgery 3 months following BRCA result disclosure, 7 of 62 women had undergone RRM and 13 of 62 women had undergone RRSO. Intent to have an RRSO prior to testing correlated with procedure uptake. In contrast, intent to undergo RRM did not correlate with uptake. Overall, reasons given for indecision about risk-reducing surgery included complex testing factors such as the significance of family history in the absence of a mutation, concerns over the surgical procedure as well as time and uncertainty regarding early menopause and the use of hormone replacement therapy.[186] In a study of patients in the United Kingdom, data were collected during observations of genetic consultations and in semistructured interviews with 41 women following their attendance at genetic counseling.[187] The option of risk-reducing surgery was raised in 29 consultations and discussed in 35 of the postclinic interviews. Fifteen women said they would consider having an oophorectomy in the future, and nine said they would consider having a mastectomy. The implications of undergoing oophorectomy and mastectomy were discussed in postclinic interviews. Risk-reducing surgery was described by the counselees as providing individuals with a means to (a) fulfill their obligations to other family members and (b) reduce risk and contain their fear of cancer. The costs of this form of risk management were described by the respondents as:

  • Compromising social obligations.
  • Upsetting the natural balance of the body.
  • Not receiving protection from cancer.
  • Operative and postoperative complications.
  • The onset of menopause.
  • The effects of body image, gender, and personal identity.
  • Potential effects on sexual relationships.[187]

A number of women choose to undergo RRM and RRSO without genetic testing because:

  • Testing is not readily accessible.
  • They do not wish exposure to the psychosocial risks of genetic testing.
  • They do not trust that a negative genetic test result means they are not at increased risk.
  • They find any level of risk, even baseline population risk, unacceptable.[188,189]

Among first-degree relatives of breast cancer patients attending a surveillance clinic, women who expressed an interest in RRM and/or had undergone surgery were found to have significantly more breast cancer biopsies (P <.05) and higher subjective 10-year breast cancer risk estimates (P <.05) than women not interested in RRM. Cancer worry at the time of entry into the clinic was highest among women who subsequently underwent RRM compared with women who expressed interest but had not yet had surgery, as well as women who did not intend to have surgery (P <.001).[190] Few studies have evaluated the impact of BRCA1/2 test results on risk-reducing surgery decisions among women affected with breast cancer. A study evaluating predictors of contralateral RRM among 435 breast cancer survivors found that 16% had undergone contralateral RRM (in conjunction with mastectomy of the affected breast) prior to referral for genetic counseling and BRCA1/2 genetic testing.[191] Predictors of contralateral RRM prior to genetic counseling and testing included younger age at breast cancer diagnosis, more time since diagnosis, having at least one affected first-degree relative, and not being employed full-time. In the year following disclosure of test results, 18% of women who tested positive for a BRCA1/2 mutation and 2% of those whose test results were uninformative underwent contralateral RRM. Predictors of contralateral RRM after genetic testing included younger age at breast cancer diagnosis, higher cancer-specific distress prior to genetic counseling, and having a positive BRCA1/2 test result. In this study, contralateral RRM was not associated with distress at one year following disclosure of genetic test results.

Dutch women (n = 114) who had undergone unilateral or bilateral RRM with breast reconstruction between 1994 and 2002 were retrospectively surveyed to determine their satisfaction with the procedure.[192] Sixty-eight percent were either unaffected BRCA mutation carriers or at 50% risk of having a BRCA mutation in their family. Sixty percent of respondents indicated that they were satisfied with the procedure, 95% would opt for RRM again, and 80% would opt for the same reconstruction procedure. Less than half reported some perioperative or postoperative complications, ongoing physical complaints, or some physical limitations. Twenty-nine percent reported altered feelings of femininity following the procedure, 44% reported adverse changes in their sexual relationships, and 35% indicated that they believed their partners experienced adverse changes in their sexual relationship. Ten percent of women, however, reported positive changes in their sexual relationship following the procedure. Compared with patients who indicated satisfaction with this procedure, nonsatisfied patients were more likely to feel less informed about the procedure and its consequences, report more complications and physical complaints, feel that their breasts did not belong to their body, and indicate that they would not opt for reconstruction again. Those who reported a negative effect on their sexual relationship were more likely to:

  • Feel less informed.
  • Experience more physical complaints and limitations.
  • Express that their breasts did not feel like their own.
  • Be disinclined to opt for reconstruction again.
  • State that the surgery had not met their expectations.
  • Experience altered feelings of femininity and perceived adverse changes in their partner's view of their femininity and their sexual relationship.

Ninety Swedish women who had undergone RRM between 1997 and 2005 were surveyed prior to surgery, 6 months after surgery, and 1 year after surgery to evaluate changes in health-related quality of life, depression, anxiety, sexuality, and body image. There were no significant changes in health-related quality of life or depression at the three time points; anxiety decreased over time (P = 0.0004). Over 80% of women reported having an intimate relationship at all three time points. Women who reported being sexually active were asked to respond to questions about sexual pleasure, discomfort, habit and frequency of activity. There were no statistically significant differences related to frequency, habit, or discomfort. However, pleasure significantly decreased between baseline and 1 year after surgery (P = 0.005). At 1 year after surgery 48% of women reported feeling less attractive, 48% reported feeling self-conscious, and 44% reported dissatisfaction with surgical scars.[193]

Discussion of risk-reducing surgical options may not consistently occur during pretest genetic counseling. In one multi-institutional study, only one-half of genetics specialists discussed RRM and RRSO in consultations with women from high-risk breast cancer families,[194,195] despite the fact that discussion of surgical options was significantly associated with meeting counselees' expectations, and that such information was not associated with increased anxiety.[196]

Given the increased risk of ovarian cancer faced by women with a BRCA1 or BRCA2 mutation, those who do receive information about RRSO show wide variations in surgery uptake (27%–72%).[89,175,180,183,184,197] A study showed that clinical factors related to choosing RRSO versus surveillance alone are older age, parity of one or more, and a prior breast cancer diagnosis.[198] In this study, the choice of RRSO was not related to family history of breast or ovarian cancer. Hysterectomy was presented as an option during genetic counseling and 80% of women who underwent RRSO also elected to have a hysterectomy.

Cancer screening and risk-reducing behaviors

Data are now emerging regarding uptake and adherence to cancer risk management recommendations such as screening and risk-reducing interventions. Cancer screening adherence and risk-reduction behaviors as defined by the National Comprehensive Cancer Network Guidelines were assessed in a cross-sectional study of 214 women with a personal history (134) or family history (80) of breast or ovarian cancer. Among unaffected women older than 40 years, 10% had not had a mammogram or clinical breast examination (CBE) in the previous year and 46% did not practice breast self-examination (BSE). Among women previously affected with breast or ovarian cancer, 21% had not had a mammogram, 32% had not had a CBE, and 39% did not practice BSE.[199]

Three hundred and twelve women who were counseled and tested for BRCA mutations between 1997 and 2005 responded to a survey regarding their perception of genetic testing for hereditary breast and ovarian cancer. The survey included questions on risk reduction options, including screening and risk-reducing surgeries. Two hundred and seventeen (70%) of the women had been diagnosed with breast cancer, and 86 (28%) tested positive for a deleterious mutation in either the BRCA1 or BRCA2 gene. None of the BRCA-positive women agreed that mammograms are difficult procedures because of the discomfort, while 11 (5.4%) of the BRCA-negative women did agree with this statement. Both groups (BRCA-positive and BRCA-negative) agreed that risk-reducing surgeries provide the best means for lowering cancer risk and worry, and most patients in both groups expressed the belief that risk-reducing mastectomy is not too drastic, too scary, or too disfiguring.[200]

A prospective study from the United Kingdom examined the psychological impact of mammographic screening in 1,286 women aged 35 to 49 years who have a family history of breast cancer and were participants in a multicenter screening program. Mammographic abnormalities that required additional evaluation were detected in 112 women. These women, however, did not show a statistically significant increase in cancer worry or negative psychological consequences as a result of these findings. The 1,174 women who had no mammographic abnormality detected experienced a decrease in cancer worry and a decrease in negative psychological consequences compared to baseline following receipt of their results. At 6 months, the entire cohort had experienced a decrease in measures of cancer worry and psychological consequences of breast screening.[201]

A qualitative study explored health care professionals' views regarding the provision of information about health protective behaviors (e.g., exercise and diet). Seven medical specialists and ten genetic counselors were interviewed during a focus group or individually. The study reported wide variation in the content and extent of information provided about health-protective behaviors and in general, participants did not consider it their role to promote such behaviors in the context of a genetic counseling session. There was agreement, however, about the need to form consensus about provision of such information both within and across risk assessment clinics.[202]

It is important to keep in mind that not all studies specify whether screening uptake rates fall within recommended guidelines for the targeted population or the specific clinical scenario, nor do they report on other variables that may influence cancer screening recommendations. For example, women who have a history of atypical ductal hyperplasia would be advised to follow screening recommendations that may differ from those of the general population.

Psychosocial Outcome Studies

Risk-reducing mastectomy

A prospective study conducted in the Netherlands found that among 26 BRCA1/2 mutation carriers, the 14 women who chose mastectomy had higher distress both before test result disclosure and 6 and 12 months later, compared with the 12 carriers who chose surveillance and compared with 53 nonmutation carriers. Overall, however, anxiety declined in women undergoing prophylactic mastectomy; at 1 year, their anxiety scores were closer to those of women choosing surveillance and to the scores of nonmutation carriers.[174] Interestingly, women opting for prophylactic mastectomy had lower pretest satisfaction with their breasts and general body image than carriers who opted for surveillance or noncarriers of BRCA1/2 mutations. Of the women who had a prophylactic mastectomy, all but one did not regret the decision at 1 year posttest disclosure, but many had difficulties with body image, sexual interest and functioning, and self-esteem. The perception that doctors had inadequately informed them about the consequences of prophylactic mastectomy was associated with regret.[174] At 5-year follow-up, women who had undergone RRM had less favorable body image and changes in sexual relationships, but also had a significant reduction in the fear of developing cancer.[91] In a study of 78 women who underwent risk-reducing surgery (including BRCA1/2 carriers and women who were from high-risk families with no detectable BRCA1/2 mutation), cancer-specific and general distress were assessed 2 weeks prior to surgery and at 6 and 12 months postsurgery.[203] The sample included women who had RRM and RRSO alone, as well as women who had both surgeries. There was no observable increase in distress over the 1-year period.

Mixed psychosocial outcomes were reported in a follow-up study (mean 14 years) of 609 women who received prophylactic mastectomies at the Mayo Clinic. Seventy percent were satisfied with prophylactic mastectomy, 11% were neutral, and 19% were dissatisfied. Eighteen percent believed that if they had the choice to make again, they probably or definitely would not have a prophylactic mastectomy. About three quarters said their worry about cancer was diminished by surgery. Half reported no change in their satisfaction with body image; 16% reported improved body image following surgery. Thirty-six percent said they were dissatisfied with their body image following prophylactic mastectomy. About a quarter of the women reported adverse impact of prophylactic mastectomy on their sexual relationships and sense of femininity, and 18% had diminished self-esteem. Factors most strongly associated with satisfaction with prophylactic mastectomy were postsurgical satisfaction with appearance, reduced stress, no reconstruction or lack of problems with implants, and no change or improvement in sexual relationships. Women who cited physician advice as the primary reason for choosing prophylactic mastectomy tended to be dissatisfied following prophylactic mastectomy.[204]

A study of 60 healthy women who underwent RRM measured levels of satisfaction, body image, sexual functioning, intrusion and avoidance, and current psychological status at a mean of 4 years and 4 months postsurgery. Of this group, 76.7% had either a strong family history (21.7%) or carried a BRCA1 or BRCA2 mutation (55%). Overall, 97% of the women surveyed were either satisfied (17%) or extremely satisfied (80%) with their decision to have RRM, and all but one participant would recommend this procedure to other women. Most women (66.7%) reported that surgery had no impact on their sexual life, although 31.7% reported a worsening sexual life, and 76.6% reported either no change in body image or an improvement in body image, regardless of whether reconstruction was performed. Worsening self-image was reported by 23.3% of women after surgery. Women's mean distress levels after surgery were only slightly above normal levels, although those women who continued to perceive their postsurgery breast cancer risk as high had higher mean levels of global and cancer-related distress than those who perceived their risk as low. Additionally, BRCA1 and BRCA2 mutation carriers and women with a strong family history of breast and/or ovarian cancer had higher mean levels of cancer-related distress than women with a limited family history.[205]

Very little is known about how the results of genetic testing affect treatment decisions at the time of cancer diagnosis. Two studies explored genetic counseling and BRCA1/2 genetic testing at the time of breast cancer diagnosis.[170,206] One of these studies found that genetic testing at the time of diagnosis significantly altered surgical decision making, with more mutation carriers than noncarriers opting for bilateral mastectomy. Bilateral RRM was chosen by 48% of mutation-positive women [170] and by 100% of mutation-positive women in a smaller series [206] of women undergoing testing at the time of diagnosis. Of women in whom no mutation was found, 24% also opted for bilateral RRM. Four percent of the test decliners also underwent bilateral RRM. Among mutation carriers, predictors of bilateral RRM included whether patients reported their physicians had recommended BRCA1/2 testing and bilateral RRM prior to testing, and whether they received a positive test result.[170] Data are lacking on quality-of-life outcomes for women undergoing RRM following genetic testing performed at the time of diagnosis.

A prospective study from the Netherlands evaluated long-term psychological outcomes of offering women with breast cancer genetic counseling and, if indicated, genetic testing at the onset of breast radiation for treatment of their primary breast cancer. Of those who were approached for counseling, some underwent genetic testing and chose to receive their result (n = 58), some were approached but did not fulfill referral criteria (n = 118), and some declined the option of counseling/testing (n = 44). Another subset of women undergoing radiation therapy was not approached for counseling (n = 182) but was followed using the same measures. Psychological distress was measured at baseline and at 4, 11, 27, and 43 weeks after initial consultation for radiation therapy. No differences were detected in general anxiety, depression or breast cancer specific-distress across all four groups.[207]

A retrospective questionnaire study of 583 women with a personal and family history of breast cancer and who underwent contralateral prophylactic mastectomy between 1960 and 1993 measured overall satisfaction after mastectomy and factors influencing satisfaction and dissatisfaction with this procedure.[208] The mean time of follow-up was 10.3 years after prophylactic surgery. Overall, 83% of all participants stated they were satisfied or very satisfied, 8% were neutral, and 9% were dissatisfied with contralateral prophylactic mastectomy. Most women also reported favorable effects or no change in their self-esteem, level of stress, and emotional stability after surgery (88%, 83%, and 88%, respectively). Despite the high levels of overall satisfaction, 33% reported negative body image, 26% reported a reduced sense of femininity, and 23% reported a negative effect on sexual relationships. The type of surgical procedure also affected levels of satisfaction. The authors attributed this difference to the high rate of unanticipated reoperations in the group of women having subcutaneous mastectomy (43%) versus the group having simple mastectomy (15%) (P <.0001). Limitations to this study are mostly related to the time period during which participants had their surgery (i.e., availability of surgical reconstructive option).[208,209] None of these women had genetic testing for mutations in the BRCA1/2 genes. Nevertheless, this study shows that while most women in this group were satisfied with contralateral prophylactic mastectomy, all women reported at least one adverse outcome.

Another study compared long-term quality-of-life outcomes in 195 women following bilateral RRM performed between 1979 and 1999 versus 117 women at high risk for breast cancer opting for screening. No statistically significant differences were detected between the groups for psychosocial outcomes. Eighty-four percent of those opting for surgery reported satisfaction with their decision. Sixty-one percent of women from both the surgery and screening groups reported being very much or quite a bit contented with their quality of life.[210]

In a study of psychosocial outcomes associated with RRM and immediate reconstruction, 61 high-risk women (27 mutation carriers, others with high-risk family history), 31 of whom had a prior history of breast cancer, were evaluated on average 3 to 4 years after surgery.[211] The study utilized questions designed to elicit yes versus no responses and found that the surgery was well-tolerated with 83% of participants reporting that the results of their reconstructive surgery were as they expected, 90% reporting that they had received adequate preoperative information, none reporting that they regretted the surgery, and all reporting that they would choose the same route if they had to do it again. Satisfaction with the results ranged from 74% satisfied with the shape of their breasts to 89% satisfied with the appearance of the scarring. Comparison of this group to normative samples on quality–of–life indicators (SF-36; HAD scores) indicated no reductions in quality of life in these women.

A qualitative study examining material on the Facing Our Risk of Cancer Empowered (FORCE) Web site posted by 21 high-risk women (BRCA1/2 positive) undergoing RRM showed that these women anticipated and received negative reactions from friends and family regarding the surgery, and that they managed disclosure in ways to maintain emotional support and self-protection for their decision. Many of the women expressed a relief from intrusive breast cancer thoughts and worry, and were satisfied with the cosmetic result of their surgery.[212]

In contrast, another study examined long-term psychosocial outcomes in 684 women who had had bilateral or contralateral RRM on average 9 years prior to assessment.[213] A majority of women (59%) had reconstructive surgery as well. Interestingly, based on a Likert scale, 85% of women reported that they were satisfied or very satisfied with their decision to have an RRM. However, in qualitative interviews, a large number of women went on to describe dissatisfaction or negative psychosocial outcomes associated with surgery. The authors coded the responses as negative when women reported still being anxious about their breast cancer risk and/or reported negative feelings about their body image, pain, and sexuality. Seventy-nine percent of the women providing negative comments and 84% of those making mixed comments (mixture of satisfaction and dissatisfaction) responded that they were either satisfied or very satisfied with their decision. Twice as many women with bilateral mastectomy made negative and mixed comments than did women with contralateral mastectomy. The areas of most concern were body image, problems with breast implants, pain after surgery, and sexuality. The authors proposed that those who had undergone contralateral procedures had already been treated for cancer, while those who had undergone bilateral procedures had not been treated previously, and this may partially account for the differences in satisfaction between the two groups. These findings suggest that women's satisfaction with RRM may be tempered by their complex reactions over time.

In a qualitative study of 108 women who underwent or were considering RRM, more than half of those who had RRM felt that pre-surgical consultation with a psychologist was advisable; nearly two-thirds thought that post-surgical consultation was also appropriate. All of the women who were considering RRM believed that psychological consultation prior to surgery would facilitate decision-making.[214]

Risk-reducing salpingo-oophorectomy

A retrospective self-administered survey of 40 women aged 35 to 74 years at time of RRSO (57.5% were younger than 50 years), who had undergone the procedure due to a family history of ovarian cancer through the Ontario Ministry of Health, found that RRSO resulted in a significant reduction in perceived ovarian cancer risk. Fifty-seven percent identified a decrease in perceived risk as a benefit of RRSO (35% did not comment on RRSO benefits) and 49% reported that they would repeat RRSO to decrease cancer risk. The overall quality-of-life scores were consistent with those published for women who are menopausal or participating in hormone studies.[215] Quality of life in 59 women who underwent RRSO was assessed at 24 months postprocedure.[216] Overall quality of life was similar to the general population and breast cancer survivors, with approximately 20% reporting depression. The 30% of subjects reporting vaginal dryness and dyspareunia were more likely to report dissatisfaction with the procedure.

Further work reported by this group found that the majority of the 127 women who had undergone RRSO 1 year previously (75 with BRCA1 mutations; 52 with BRCA2 mutations) felt that RRSO reduced their risk of both breast and ovarian cancer.[217] There was a wide range of risk perceptions for ovarian cancer noted in the group. Twenty percent of BRCA1 and BRCA2 mutation carriers thought that their risk for ovarian cancer was completely eliminated; others had an inflated perception of their ovarian cancer risk both before and after surgery. A small group of these women were further surveyed at about 3 years post surgery and their risk perceptions did not change significantly over this extended time period. These findings suggest that important misperceptions about ovarian cancer risk may persist after RRSO. Additional genetic education and counseling may be warranted.

A larger study assessed quality of life in women at high risk of ovarian cancer who opted for periodic gynecologic screening (GS) versus those who underwent RRSO. Eight hundred forty-six high-risk women, 44% of whom underwent RRSO and 56% of whom chose GS, completed questionnaires evaluating quality of life, cancer-specific distress, endocrine symptoms, and sexual functioning.[218] Women in the RRSO group were a mean of 2.8 ±1.9 years from surgery and women in the GS group were a mean of 4.3 years from their first visit to a gynecologist for high-risk management. No statistical difference in overall quality of life was detected between the RRSO and GS groups. When compared with the GS group, women who underwent RRSO had poorer sexual functioning and more endocrine symptoms such as vaginal dryness, dyspareunia, and hot flashes. Women who underwent RRSO experienced lower levels of breast and ovarian cancer distress and had a more favorable perception of cancer risk.

Interventions: Psychological

Several psychological interventions have been proposed for women who may have hereditary risk of breast cancer, but few of these have been rigorously tested. Issues faced by these women include the following:

  • Confronting the meaning of one's risk status, as well as venting strong feelings of fear of harm, disfigurement, pain, or death.
  • Addressing guilt about passing on genetic risk or not doing enough for loved ones.
  • Managing stress, cancer-related worry, and intrusive thoughts.
  • Coaching in problem-solving.
  • Facilitating effective decision-making strategies and teaching positive, active coping behaviors.

Psychotherapy for women interested in prophylactic mastectomy is discussed in one report.[219] Another recommends rehearsal of affective state in the context of all potential outcomes of cancer genetic testing for BRCA1/2.[220] As genetic testing programs grow and the psychological outcomes and behavioral impact of testing are further defined, there will be an increasing demand for interventions to maximize the benefits of cancer genetic testing and minimize the risks to carriers and family members.

A randomized trial with 126 BRCA1/2 mutation carriers evaluated whether psychological and behavioral outcomes of BRCA1/2 testing are improved among mutation carriers by providing a psychosocial telephone counseling intervention in addition to standard genetic counseling.[221] The intervention consisted of five 60- to 90-minute telephone counseling sessions. The first session was a semistructured clinical assessment interview designed to allow the mutation carrier to describe her experiences and reactions to BRCA testing results. The second through the fourth telephone sessions were individualized to the concerns raised by the woman in the domains of making medical decisions, managing family concerns, and emotional reactions following receipt of a positive BRCA1/2 result. The final telephone session focused on integration and closure on the issues raised as well as implementing a plan for short-term and long-term goals established during the telephone intervention. Women most likely to complete the intervention were those who did not have a personal history of cancer; those who had higher levels of cancer-specific distress; those who were college graduates; and those who were employed. Outcome data from this study has not yet been reported.

A pilot study demonstrated the usefulness of a 6-session psychoeducational support group for women at high genetic risk of breast cancer who were considering prophylactic mastectomy. The themes for the group sessions included overestimation of and anxiety about risk, desire for hard data, emotional impact of watching a mother die of breast cancer, concerns about spouse reactions, self-image and body image, the decision-making process, and confusion over whom to trust in decision-making. Both the participants and the multidisciplinary leaders concluded that as a supplement to individual counseling, a support group is a beneficial and cost-effective treatment modality.[222]

Women who called the NCI's Cancer Information Service seeking information about breast or ovarian cancer risk, risk assessment, or cancer genetic testing, were randomly assigned to receive 1) general information about cancer risk and a referral to testing and counseling services or 2) an educational intervention designed to increase knowledge and understanding about inherited cancer risk, personal history of cancer, and the benefits and limitations of genetic testing. In the group receiving the educational intervention, intention to obtain genetic testing decreased among women at average breast cancer risk (as determined by the Gail model) and increased among women at high risk. Among average risk women, those in the intervention group identified as high monitors (i.e., those who seek and pay greater attention to threatening health-related information) demonstrated an increase in knowledge and breast cancer risk perceptions compared with low monitors (i.e., those who avoid attending to threatening health-related information).[223]

Behavioral Outcomes

A study [224] of screening behaviors of 216 self-referred, high-risk (>10% risk of carrying a BRCA1/2 mutation) women who are members of hereditary breast cancer families found a range of screening practices. Even the presence of known mutations in their families was not associated with good adherence to recommended screening practices. Sixty-nine percent of women aged 50 to 64 years and 83% of women aged 40 to 49 years had had a screening mammogram in the previous year. Twenty percent of participants had ever had a CA 125 test and 31% had ever had a pelvic or transvaginal ultrasound. Further analysis of this study population [224] looking specifically at 107 women with informative BRCA test results found good use of breast cancer screening, though the uptake rate in younger carriers is lower. The reason for the lower uptake rate was not explored in this study.[225] One survey of screening behaviors among women at increased risk of breast/ovarian cancer identified physician recommendations as a significant factor in adherence to screening.[226]

While motivations cited for pursuing genetic testing often include the expectation that mutation carriers will be more compliant with breast and/or ovarian screening recommendations,[27,29,224,227] limited data exist about whether participants in genetic testing alter their screening behaviors over time and about other variables that may influence those behaviors, such as insurance coverage and physician recommendations or attitudes. The impact of cancer genetic counseling on screening behaviors was assessed in a U.K. study of 293 women followed for 12 months postcounseling at four cancer genetics clinics.[228] BSE, CBE, and mammography were significantly increased after counseling; however, gaps in adherence to recommendations were noted: 38% of women aged 35 to 49 years had not had a mammogram by 12 months postcounseling. BSE was not done at the recommended time and frequency by most women.

This is a critical issue not only for women testing positive, but also for adherence to screening for those testing negative as well as those who have received indeterminate results or choose not to receive their results. It is possible that adherence actually diminishes with a decrease in the perceived risk that may result from a negative genetic test result.

In addition, while there is still some question regarding the link between cancer-related worry and breast cancer screening behavior, accumulating evidence appears to support a linear rather than a curvilinear relationship. That is, for some time, the data were not consistent; some data supported the hypothesis that mild-to-moderate worry may increase adherence, while excessive worry may actually decrease the utilization of recommended screening practices. Other reports support the notion that a linear relationship is more likely; that is, more worry increases adherence to screening recommendations. Few studies, however, have followed women to assess their health behaviors following genetic testing. Thus, a negative test result leading to decreased worry could theoretically result in decreased screening adherence. A large study found that patient compliance with screening practices was not related to general or screening-specific anxiety—with the exception of BSE, for which compliance is negatively associated with procedure-specific anxiety.[49] Further research designed to clarify this potential concern would highlight the need for comprehensive genetic counseling to discuss the need for follow-up screening.

Further complicating this area of research are issues such as the baseline rate of mammography adherence among women older than 40 or 50 years prior to genetic testing. More specifically, the ability to note a significant difference in adherence on this measure may be affected by the high adherence rate to this screening behavior before genetic testing by women undergoing such testing. It may be easier to find significant changes in mammography use among women with a family history of breast cancer who test positive. Finally, adherence over time will likely be affected by how women undergoing genetic testing and their caregivers perceive the efficacy of many of the screening options in question, such as mammography for younger women, BSE, and ovarian cancer screening (periodic vaginal ultrasound and serum CA 125 measurements), along with the value of preventive interventions.

The issue of screening decision-making and adherence among women undergoing genetic testing for breast and ovarian cancer is the subject of several ongoing trials, and an area of much needed ongoing study.

References:

1. Lynch HT, Fitzsimmons ML, Lynch J, et al.: A hereditary cancer consultation clinic. Nebr Med J 74 (12): 351-9, 1989.
2. Eeles RA, ed.: Genetic Predisposition to Cancer. London, England: Chapman and Hall Medical, 1996.
3. Baty BJ, Venne VL, McDonald J, et al.: BRCA1 testing: genetic counseling protocol development and counseling issues. J Genet Couns 6(2): 223-244, 1997.
4. Hoskins IA: Genetic counseling for cancer patients and their families. Oncology (Huntingt) 3 (1): 84-92; discussion 92, 95-8, 1989.
5. Lynch HT, Lynch J: Genetic counseling for hereditary cancer. Oncology (Huntingt) 10 (1): 27-34, 1996.
6. McKinnon WC, Guttmacher AE, Greenblatt MS, et al.: The Familial Cancer Program of the Vermont Cancer Center: development of a cancer genetics program in a rural area. J Genet Couns 6(2): 131-145, 1997.
7. Offit K: Clinical Cancer Genetics: Risk Counseling and Management. New York, NY: John Wiley and Sons, 1998.
8. Peters JA: Familial cancer risk, part II: breast cancer risk counseling and genetic susceptibility testing. J Oncol Manag 3 (6): 14-22, 1994.
9. Ponder BA: Setting up and running a familial cancer clinic. Br Med Bull 50 (3): 732-45, 1994.
10. Collins FS, Thomson EJ: Findings from the cancer genetic studies consortium. Cancer Epidemiol Biomarkers Prev 8 (special issue): 325, 1999.
11. Calzone KA, Biesecker BB: Genetic testing for cancer predisposition. Cancer Nurs 25 (1): 15-25; quiz 26-7, 2002.
12. Ropka ME, Wenzel J, Phillips EK, et al.: Uptake rates for breast cancer genetic testing: a systematic review. Cancer Epidemiol Biomarkers Prev 15 (5): 840-55, 2006.
13. Metcalfe KA, Fan I, McLaughlin J, et al.: Uptake of clinical genetic testing for ovarian cancer in Ontario: a population-based study. Gynecol Oncol 112 (1): 68-72, 2009.
14. Bowen DJ, Patenaude AF, Vernon SW: Psychosocial issues in cancer genetics: from the laboratory to the public. Cancer Epidemiol Biomarkers Prev 8 (4 Pt 2): 326-8, 1999.
15. Lee SC, Bernhardt BA, Helzlsouer KJ: Utilization of BRCA1/2 genetic testing in the clinical setting: report from a single institution. Cancer 94 (6): 1876-85, 2002.
16. Durfy SJ, Buchanan TE, Burke W: Testing for inherited susceptibility to breast cancer: a survey of informed consent forms for BRCA1 and BRCA2 mutation testing. Am J Med Genet 75 (1): 82-7, 1998.
17. Geller G, Doksum T, Bernhardt BA, et al.: Participation in breast cancer susceptibility testing protocols: influence of recruitment source, altruism, and family involvement on women's decisions. Cancer Epidemiol Biomarkers Prev 8 (4 Pt 2): 377-83, 1999.
18. Kash KM, Holland JC, Halper MS, et al.: Psychological distress and surveillance behaviors of women with a family history of breast cancer. J Natl Cancer Inst 84 (1): 24-30, 1992.
19. Lerman C, Schwartz M: Adherence and psychological adjustment among women at high risk for breast cancer. Breast Cancer Res Treat 28 (2): 145-55, 1993.
20. Armstrong K, Calzone K, Stopfer J, et al.: Factors associated with decisions about clinical BRCA1/2 testing. Cancer Epidemiol Biomarkers Prev 9 (11): 1251-4, 2000.
21. Armstrong K, Stopfer J, Calzone K, et al.: What does my doctor think? Preferences for knowing the doctor's opinion among women considering clinical testing for BRCA1/2 mutations. Genet Test 6 (2): 115-8, 2002 Summer.
22. Shannon KM, Muzikansky A, Chan-Smutko G, et al.: Uptake of BRCA1 rearrangement panel testing: in individuals previously tested for BRCA1/2 mutations. Genet Med 8 (12): 740-5, 2006.
23. Lerman C, Hughes C, Lemon SJ, et al.: What you don't know can hurt you: adverse psychologic effects in members of BRCA1-linked and BRCA2-linked families who decline genetic testing. J Clin Oncol 16 (5): 1650-4, 1998.
24. Lodder L, Frets PG, Trijsburg RW, et al.: Attitudes and distress levels in women at risk to carry a BRCA1/BRCA2 gene mutation who decline genetic testing. Am J Med Genet 119A (3): 266-72, 2003.
25. Foster C, Evans DG, Eeles R, et al.: Non-uptake of predictive genetic testing for BRCA1/2 among relatives of known carriers: attributes, cancer worry, and barriers to testing in a multicenter clinical cohort. Genet Test 8 (1): 23-9, 2004.
26. McInerney-Leo A, Biesecker BB, Hadley DW, et al.: BRCA1/2 testing in hereditary breast and ovarian cancer families II: impact on relationships. Am J Med Genet A 133 (2): 165-9, 2005.
27. Struewing JP, Lerman C, Kase RG, et al.: Anticipated uptake and impact of genetic testing in hereditary breast and ovarian cancer families. Cancer Epidemiol Biomarkers Prev 4 (2): 169-73, 1995.
28. Rimer BK, Schildkraut JM, Lerman C, et al.: Participation in a women's breast cancer risk counseling trial. Who participates? Who declines? High Risk Breast Cancer Consortium. Cancer 77 (11): 2348-55, 1996.
29. Jacobsen PB, Valdimarsdottier HB, Brown KL, et al.: Decision-making about genetic testing among women at familial risk for breast cancer. Psychosom Med 59 (5): 459-66, 1997 Sep-Oct.
30. Lerman C, Hughes C, Benkendorf JL, et al.: Racial differences in testing motivation and psychological distress following pretest education for BRCA1 gene testing. Cancer Epidemiol Biomarkers Prev 8 (4 Pt 2): 361-7, 1999.
31. Durfy SJ, Bowen DJ, McTiernan A, et al.: Attitudes and interest in genetic testing for breast and ovarian cancer susceptibility in diverse groups of women in western Washington. Cancer Epidemiol Biomarkers Prev 8 (4 Pt 2): 369-75, 1999.
32. Evans DG, Binchy A, Shenton A, et al.: Comparison of proactive and usual approaches to offering predictive testing for BRCA1/2 mutations in unaffected relatives. Clin Genet 75 (2): 124-32, 2009.
33. Kessler L, Collier A, Brewster K, et al.: Attitudes about genetic testing and genetic testing intentions in African American women at increased risk for hereditary breast cancer. Genet Med 7 (4): 230-8, 2005.
34. Armstrong K, Micco E, Carney A, et al.: Racial differences in the use of BRCA1/2 testing among women with a family history of breast or ovarian cancer. JAMA 293 (14): 1729-36, 2005.
35. Winer E, Winer N, Bluman L, et al.: Attitudes and risk perceptions of women with breast cancer considering testing for BRCA1/2. [Abstract] Proceedings of the American Society of Clinical Oncology 16: A1937, 537a, 1997.
36. Braithwaite D, Emery J, Walter F, et al.: Psychological impact of genetic counseling for familial cancer: a systematic review and meta-analysis. J Natl Cancer Inst 96 (2): 122-33, 2004.
37. Mikkelsen EM, Sunde L, Johansen C, et al.: Psychosocial conditions of women awaiting genetic counseling: a population-based study. J Genet Couns 17 (3): 242-51, 2008.
38. Dorval M, Bouchard K, Maunsell E, et al.: Health behaviors and psychological distress in women initiating BRCA1/2 genetic testing: comparison with control population. J Genet Couns 17 (4): 314-26, 2008.
39. Hallowell N, Statham H, Murton F: Women's understanding of their risk of developing breast/ovarian cancer before and after genetic counseling. J Genet Couns 7(4): 345-364, 1998.
40. MacDonald DJ, Choi J, Ferrell B, et al.: Concerns of women presenting to a comprehensive cancer centre for genetic cancer risk assessment. J Med Genet 39 (7): 526-30, 2002.
41. Matloff ET, Moyer A, Shannon KM, et al.: Healthy women with a family history of breast cancer: impact of a tailored genetic counseling intervention on risk perception, knowledge, and menopausal therapy decision making. J Womens Health (Larchmt) 15 (7): 843-56, 2006.
42. Bluman LG, Rimer BK, Berry DA, et al.: Attitudes, knowledge, and risk perceptions of women with breast and/or ovarian cancer considering testing for BRCA1 and BRCA2. J Clin Oncol 17 (3): 1040-6, 1999.
43. Iglehart JD, Miron A, Rimer BK, et al.: Overestimation of hereditary breast cancer risk. Ann Surg 228 (3): 375-84, 1998.
44. Bluman LG, Rimer BK, Regan Sterba K, et al.: Attitudes, knowledge, risk perceptions and decision-making among women with breast and/or ovarian cancer considering testing for BRCA1 and BRCA2 and their spouses. Psychooncology 12 (5): 410-27, 2003 Jul-Aug.
45. McCaul KD, O'Donnell SM: Naive beliefs about breast cancer risk. Womens Health 4 (1): 93-101, 1998 Spring.
46. Huiart L, Eisinger F, Stoppa-Lyonnet D, et al.: Effects of genetic consultation on perception of a family risk of breast/ovarian cancer and determinants of inaccurate perception after the consultation. J Clin Epidemiol 55 (7): 665-75, 2002.
47. Davis S, Stewart S, Bloom J: Increasing the accuracy of perceived breast cancer risk: results from a randomized trial with Cancer Information Service callers. Prev Med 39 (1): 64-73, 2004.
48. Katapodi MC, Dodd MJ, Lee KA, et al.: Underestimation of breast cancer risk: influence on screening behavior. Oncol Nurs Forum 36 (3): 306-14, 2009.
49. Lindberg NM, Wellisch D: Anxiety and compliance among women at high risk for breast cancer. Ann Behav Med 23 (4): 298-303, 2001 Fall.
50. Ritvo P, Irvine J, Robinson G, et al.: Psychological adjustment to familial-genetic risk assessment for ovarian cancer: predictors of nonadherence to surveillance recommendations. Gynecol Oncol 84 (1): 72-80, 2002.
51. Meiser B, Halliday JL: What is the impact of genetic counselling in women at increased risk of developing hereditary breast cancer? A meta-analytic review. Soc Sci Med 54 (10): 1463-70, 2002.
52. Green J, Richards M, Murton F, et al.: Family communication and genetic counseling: the case of hereditary breast and ovarian cancer. J Genet Couns 6(1): 45-60, 1997.
53. Quillin JM, Ramakrishnan V, Borzelleca J, et al.: Paternal relatives and family history of breast cancer. Am J Prev Med 31 (3): 265-8, 2006.
54. Theis B, Boyd N, Lockwood G, et al.: Accuracy of family cancer history in breast cancer patients. Eur J Cancer Prev 3 (4): 321-7, 1994.
55. Breuer B, Kash KM, Rosenthal G, et al.: Reporting bilaterality status in first-degree relatives with breast cancer: a validity study. Genet Epidemiol 10 (4): 245-56, 1993.
56. Parent ME, Ghadirian P, Lacroix A, et al.: The reliability of recollections of family history: implications for the medical provider. J Cancer Educ 12 (2): 114-20, 1997 Summer.
57. Kelly KM, Shedlosky-Shoemaker R, Porter K, et al.: Cancer family history reporting: impact of method and psychosocial factors. J Genet Couns 16 (3): 373-82, 2007.
58. Kerber RA, Slattery ML: Comparison of self-reported and database-linked family history of cancer data in a case-control study. Am J Epidemiol 146 (3): 244-8, 1997.
59. Kerr B, Foulkes WD, Cade D, et al.: False family history of breast cancer in the family cancer clinic. Eur J Surg Oncol 24 (4): 275-9, 1998.
60. Schwartz MD, Peshkin BN, Hughes C, et al.: Impact of BRCA1/BRCA2 mutation testing on psychologic distress in a clinic-based sample. J Clin Oncol 20 (2): 514-20, 2002.
61. Mancini J, Noguès C, Adenis C, et al.: Impact of an information booklet on satisfaction and decision-making about BRCA genetic testing. Eur J Cancer 42 (7): 871-81, 2006.
62. Green MJ, Biesecker BB, McInerney AM, et al.: An interactive computer program can effectively educate patients about genetic testing for breast cancer susceptibility. Am J Med Genet 103 (1): 16-23, 2001.
63. Green MJ, Peterson SK, Baker MW, et al.: Effect of a computer-based decision aid on knowledge, perceptions, and intentions about genetic testing for breast cancer susceptibility: a randomized controlled trial. JAMA 292 (4): 442-52, 2004.
64. Green MJ, McInerney AM, Biesecker BB, et al.: Education about genetic testing for breast cancer susceptibility: patient preferences for a computer program or genetic counselor. Am J Med Genet 103 (1): 24-31, 2001.
65. Dabney MK, Huelsman K: Counseling by computer: breast cancer risk and genetic testing. Developed by the University of Wisconsin-Madison Department of Medicine and the Program in Medical Ethics. Genet Test 4 (1): 43-4, 2000.
66. Green MJ, Peterson SK, Baker MW, et al.: Use of an educational computer program before genetic counseling for breast cancer susceptibility: effects on duration and content of counseling sessions. Genet Med 7 (4): 221-9, 2005.
67. Baty BJ, Kinney AY, Ellis SM: Developing culturally sensitive cancer genetics communication aids for African Americans. Am J Med Genet 118A (2): 146-55, 2003.
68. Calzone KA: Predisposition testing for breast and ovarian cancer susceptibility. Semin Oncol Nurs 13 (2): 82-90, 1997.
69. Smith KR, West JA, Croyle RT, et al.: Familial context of genetic testing for cancer susceptibility: moderating effect of siblings' test results on psychological distress one to two weeks after BRCA1 mutation testing. Cancer Epidemiol Biomarkers Prev 8 (4 Pt 2): 385-92, 1999.
70. Wylie JE, Smith KR, Botkin JR: Effects of spouses on distress experienced by BRCA1 mutation carriers over time. Am J Med Genet 119C (1): 35-44, 2003.
71. Kelly PT: Understanding Breast Cancer Risk. Philadelphia, Pa: Temple University Press, 1991.
72. Hubbard R, Lewontin RC: Pitfalls of genetic testing. N Engl J Med 334 (18): 1192-4, 1996.
73. Richards MP, Hallowell N, Green JM, et al.: Counseling families with hereditary breast and ovarian cancer: a psychosocial perspective. J Genet Couns 4(3): 219-233, 1995.
74. Hoskins KF, Stopfer JE, Calzone KA, et al.: Assessment and counseling for women with a family history of breast cancer. A guide for clinicians. JAMA 273 (7): 577-85, 1995.
75. Schneider KA: Genetic counseling for BRCA1/BRCA2 testing. Genet Test 1 (2): 91-8, 1997.
76. McKinnon WC, Baty BJ, Bennett RL, et al.: Predisposition genetic testing for late-onset disorders in adults. A position paper of the National Society of Genetic Counselors. JAMA 278 (15): 1217-20, 1997.
77. Cummings S, Olopade O: Predisposition testing for inherited breast cancer. Oncology (Huntingt) 12 (8): 1227-41; discussion 1241-2, 1998.
78. Lipkus IM, Klein WM, Rimer BK: Communicating breast cancer risks to women using different formats. Cancer Epidemiol Biomarkers Prev 10 (8): 895-8, 2001.
79. Butow PN, Lobb EA: Analyzing the process and content of genetic counseling in familial breast cancer consultations. J Genet Couns 13 (5): 403-24, 2004.
80. Lerman C, Audrain J, Croyle RT: DNA-testing for heritable breast cancer risks: lessons from traditional genetic counseling. Ann Behav Med 16(4): 327-333, 1994.
81. Pieterse AH, van Dulmen AM, Beemer FA, et al.: Cancer genetic counseling: communication and counselees' post-visit satisfaction, cognitions, anxiety, and needs fulfillment. J Genet Couns 16 (1): 85-96, 2007.
82. Struewing JP, Hartge P, Wacholder S, et al.: The risk of cancer associated with specific mutations of BRCA1 and BRCA2 among Ashkenazi Jews. N Engl J Med 336 (20): 1401-8, 1997.
83. Lerman C, Narod S, Schulman K, et al.: BRCA1 testing in families with hereditary breast-ovarian cancer. A prospective study of patient decision making and outcomes. JAMA 275 (24): 1885-92, 1996.
84. Croyle RT, Smith KR, Botkin JR, et al.: Psychological responses to BRCA1 mutation testing: preliminary findings. Health Psychol 16 (1): 63-72, 1997.
85. Reichelt JG, Heimdal K, Møller P, et al.: BRCA1 testing with definitive results: a prospective study of psychological distress in a large clinic-based sample. Fam Cancer 3 (1): 21-8, 2004.
86. Reichelt JG, Møller P, Heimdal K, et al.: Psychological and cancer-specific distress at 18 months post-testing in women with demonstrated BRCA1 mutations for hereditary breast/ovarian cancer. Fam Cancer 7 (3): 245-54, 2008.
87. Broadstock M, Michie S, Marteau T: Psychological consequences of predictive genetic testing: a systematic review. Eur J Hum Genet 8 (10): 731-8, 2000.
88. Watson M, Foster C, Eeles R, et al.: Psychosocial impact of breast/ovarian (BRCA1/2) cancer-predictive genetic testing in a UK multi-centre clinical cohort. Br J Cancer 91 (10): 1787-94, 2004.
89. Foster C, Watson M, Eeles R, et al.: Predictive genetic testing for BRCA1/2 in a UK clinical cohort: three-year follow-up. Br J Cancer 96 (5): 718-24, 2007.
90. Claes E, Evers-Kiebooms G, Denayer L, et al.: Predictive genetic testing for hereditary breast and ovarian cancer: psychological distress and illness representations 1 year following disclosure. J Genet Couns 14 (5): 349-63, 2005.
91. van Oostrom I, Meijers-Heijboer H, Lodder LN, et al.: Long-term psychological impact of carrying a BRCA1/2 mutation and prophylactic surgery: a 5-year follow-up study. J Clin Oncol 21 (20): 3867-74, 2003.
92. Horowitz M, Wilner N, Alvarez W: Impact of Event Scale: a measure of subjective stress. Psychosom Med 41 (3): 209-18, 1979.
93. DudokdeWit AC, Tibben A, Duivenvoorden HJ, et al.: Predicting adaptation to presymptomatic DNA testing for late onset disorders: who will experience distress? Rotterdam Leiden Genetics Workgroup. J Med Genet 35 (9): 745-54, 1998.
94. Andrews L, Meiser B, Apicella C, et al.: Psychological impact of genetic testing for breast cancer susceptibility in women of Ashkenazi Jewish background: a prospective study. Genet Test 8 (3): 240-7, 2004.
95. Wood ME, Mullineaux L, Rahm AK, et al.: Impact of BRCA1 testing on women with cancer: a pilot study. Genet Test 4 (3): 265-72, 2000.
96. Coyne JC, Kruus L, Racioppo M, et al.: What do ratings of cancer-specific distress mean among women at high risk of breast and ovarian cancer? Am J Med Genet 116A (3): 222-8, 2003.
97. DudokdeWit AC, Tibben A, Frets PG, et al.: BRCA1 in the family: a case description of the psychological implications. Am J Med Genet 71 (1): 63-71, 1997.
98. Macke E: A family history of breast and ovarian cancer. In: Marteau T, Richards M, eds.: The Troubled Helix: Social and Psychological Implications of the New Human Genetics. Cambridge, England: Cambridge University Press, 1996, pp 31-37.
99. Bonadona V, Saltel P, Desseigne F, et al.: Cancer patients who experienced diagnostic genetic testing for cancer susceptibility: reactions and behavior after the disclosure of a positive test result. Cancer Epidemiol Biomarkers Prev 11 (1): 97-104, 2002.
100. Bish A, Sutton S, Jacobs C, et al.: Changes in psychological distress after cancer genetic counselling: a comparison of affected and unaffected women. Br J Cancer 86 (1): 43-50, 2002 Jan 7.
101. Dorval M, Patenaude AF, Schneider KA, et al.: Anticipated versus actual emotional reactions to disclosure of results of genetic tests for cancer susceptibility: findings from p53 and BRCA1 testing programs. J Clin Oncol 18 (10): 2135-42, 2000.
102. Hallowell N, Foster C, Ardern-Jones A, et al.: Genetic testing for women previously diagnosed with breast/ovarian cancer: examining the impact of BRCA1 and BRCA2 mutation searching. Genet Test 6 (2): 79-87, 2002 Summer.
103. Brain K, Norman P, Gray J, et al.: A randomized trial of specialist genetic assessment: psychological impact on women at different levels of familial breast cancer risk. Br J Cancer 86 (2): 233-8, 2002.
104. Fry A, Cull A, Appleton S, et al.: A randomised controlled trial of breast cancer genetics services in South East Scotland: psychological impact. Br J Cancer 89 (4): 653-9, 2003.
105. Bernhardt BA, Geller G, Doksum T, et al.: Evaluation of nurses and genetic counselors as providers of education about breast cancer susceptibility testing. Oncol Nurs Forum 27 (1): 33-9, 2000 Jan-Feb.
106. Hallowell N, Statham H, Murton F, et al.: "Talking about chance": the presentation of risk information during genetic counseling for breast and ovarian cancer. J Genet Couns 6(3): 269-286, 1997.
107. Audrain J, Rimer B, Cella D, et al.: Genetic counseling and testing for breast-ovarian cancer susceptibility: what do women want? J Clin Oncol 16 (1): 133-8, 1998.
108. Watson M, Duvivier V, Wade Walsh M, et al.: Family history of breast cancer: what do women understand and recall about their genetic risk? J Med Genet 35 (9): 731-8, 1998.
109. Wakefield CE, Meiser B, Homewood J, et al.: A randomized controlled trial of a decision aid for women considering genetic testing for breast and ovarian cancer risk. Breast Cancer Res Treat 107 (2): 289-301, 2008.
110. Lerman C, Peshkin BN, Hughes C, et al.: Family disclosure in genetic testing for cancer susceptibility: determinants and consequences. Journal of Health Care Law and Policy 1(2): 353-373, 1998.
111. Kenen R, Arden-Jones A, Eeles R: Healthy women from suspected hereditary breast and ovarian cancer families: the significant others in their lives. Eur J Cancer Care (Engl) 13 (2): 169-79, 2004.
112. Finlay E, Stopfer JE, Burlingame E, et al.: Factors determining dissemination of results and uptake of genetic testing in families with known BRCA1/2 mutations. Genet Test 12 (1): 81-91, 2008.
113. Hughes C, Lerman C, Schwartz M, et al.: All in the family: evaluation of the process and content of sisters' communication about BRCA1 and BRCA2 genetic test results. Am J Med Genet 107 (2): 143-50, 2002.
114. Wagner Costalas J, Itzen M, Malick J, et al.: Communication of BRCA1 and BRCA2 results to at-risk relatives: a cancer risk assessment program's experience. Am J Med Genet 119C (1): 11-8, 2003.
115. Patenaude AF, Dorval M, DiGianni LS, et al.: Sharing BRCA1/2 test results with first-degree relatives: factors predicting who women tell. J Clin Oncol 24 (4): 700-6, 2006.
116. MacDonald DJ, Sarna L, van Servellen G, et al.: Selection of family members for communication of cancer risk and barriers to this communication before and after genetic cancer risk assessment. Genet Med 9 (5): 275-82, 2007.
117. Claes E, Evers-Kiebooms G, Boogaerts A, et al.: Communication with close and distant relatives in the context of genetic testing for hereditary breast and ovarian cancer in cancer patients. Am J Med Genet 116A (1): 11-9, 2003.
118. Foster C, Eeles R, Ardern-Jones A, et al.: Juggling roles and expectations: dilemmas faced by women talking to relatives about cancer and genetic testing. Psychol Health 19 (4): 439-55, 2004.
119. Kenen R, Arden-Jones A, Eeles R: We are talking, but are they listening? Communication patterns in families with a history of breast/ovarian cancer (HBOC). Psychooncology 13 (5): 335-45, 2004.
120. Segal J, Esplen MJ, Toner B, et al.: An investigation of the disclosure process and support needs of BRCA1 and BRCA2 carriers. Am J Med Genet A 125 (3): 267-72, 2004.
121. Bradbury AR, Dignam JJ, Ibe CN, et al.: How often do BRCA mutation carriers tell their young children of the family's risk for cancer? A study of parental disclosure of BRCA mutations to minors and young adults. J Clin Oncol 25 (24): 3705-11, 2007.
122. Bradbury AR, Patrick-Miller L, Pawlowski K, et al.: Learning of your parent's BRCA mutation during adolescence or early adulthood: a study of offspring experiences. Psychooncology 18 (2): 200-8, 2009.
123. Manne S, Audrain J, Schwartz M, et al.: Associations between relationship support and psychological reactions of participants and partners to BRCA1 and BRCA2 testing in a clinic-based sample. Ann Behav Med 28 (3): 211-25, 2004.
124. McAllister MF, Evans DG, Ormiston W, et al.: Men in breast cancer families: a preliminary qualitative study of awareness and experience. J Med Genet 35 (9): 739-44, 1998.
125. Liede A, Metcalfe K, Hanna D, et al.: Evaluation of the needs of male carriers of mutations in BRCA1 or BRCA2 who have undergone genetic counseling. Am J Hum Genet 67 (6): 1494-504, 2000.
126. Metcalfe KA, Liede A, Trinkaus M, et al.: Evaluation of the needs of spouses of female carriers of mutations in BRCA1 and BRCA2. Clin Genet 62 (6): 464-9, 2002.
127. Mireskandari S, Sherman KA, Meiser B, et al.: Psychological adjustment among partners of women at high risk of developing breast/ovarian cancer. Genet Med 9 (5): 311-20, 2007.
128. Daly MB: The impact of social roles on the experience of men in BRCA1/2 families: implications for counseling. J Genet Couns 18 (1): 42-8, 2009.
129. DudokdeWit AC, Tibben A, Frets PG, et al.: Males at-risk for the BRCA1 gene, the psychological impact. Psychooncology 5(3): 251-257, 1996.
130. Lodder L, Frets PG, Trijsburg RW, et al.: Men at risk of being a mutation carrier for hereditary breast/ovarian cancer: an exploration of attitudes and psychological functioning during genetic testing. Eur J Hum Genet 9 (7): 492-500, 2001.
131. Lerman C, Hughes C, Croyle RT, et al.: Prophylactic surgery decisions and surveillance practices one year following BRCA1/2 testing. Prev Med 31 (1): 75-80, 2000.
132. Hughes C, Lynch H, Durham C, et al.: Communication of BRCA1/2 Test Results in Hereditary Breast Cancer Families. Cancer Research in Therapy and Control Vol. 8, 1999, pp. 51-59.
133. Tercyak KP, Hughes C, Main D, et al.: Parental communication of BRCA1/2 genetic test results to children. Patient Educ Couns 42 (3): 213-24, 2001.
134. Tercyak KP, Peshkin BN, DeMarco TA, et al.: Parent-child factors and their effect on communicating BRCA1/2 test results to children. Patient Educ Couns 47 (2): 145-53, 2002.
135. McGivern B, Everett J, Yager GG, et al.: Family communication about positive BRCA1 and BRCA2 genetic test results. Genet Med 6 (6): 503-9, 2004 Nov-Dec.
136. Tercyak KP, Peshkin BN, Demarco TA, et al.: Information needs of mothers regarding communicating BRCA1/2 cancer genetic test results to their children. Genet Test 11 (3): 249-55, 2007.
137. Patenaude AF: Cancer susceptibility testing: risks, benefits, and personal beliefs. In: Clarke A, ed.: The Genetic Testing of Children. Oxford, England: BIOS Scientific, 1998, pp 145-156.
138. Richards M: The genetic testing of children: adult attitude's and children's understanding. In: Clarke A, ed.: The Genetic Testing of Children. Oxford, England: BIOS Scientific, 1998, pp 169-179.
139. Wertz DC, Fanos JH, Reilly PR: Genetic testing for children and adolescents. Who decides? JAMA 272 (11): 875-81, 1994.
140. Borry P, Stultiëns L, Nys H, et al.: Attitudes towards predictive genetic testing in minors for familial breast cancer: a systematic review. Crit Rev Oncol Hematol 64 (3): 173-81, 2007.
141. Wertz DC: International perspectives. In: Clarke A, ed.: The Genetic Testing of Children. Oxford, England: BIOS Scientific, 1998, pp 271-287.
142. Benkendorf JL, Reutenauer JE, Hughes CA, et al.: Patients' attitudes about autonomy and confidentiality in genetic testing for breast-ovarian cancer susceptibility. Am J Med Genet 73 (3): 296-303, 1997.
143. Points to consider: ethical, legal, and psychosocial implications of genetic testing in children and adolescents. American Society of Human Genetics Board of Directors, American College of Medical Genetics Board of Directors. Am J Hum Genet 57 (5): 1233-41, 1995.
144. Michie S, Marteau TM: Predictive genetic testing in children: the need for psychological research. In: Clarke A, ed.: The Genetic Testing of Children. Oxford, England: BIOS Scientific, 1998, pp 169-182.
145. MacDonald DJ, Lessick M: Hereditary cancers in children and ethical and psychosocial implications. J Pediatr Nurs 15 (4): 217-25, 2000.
146. Tercyak KP, Peshkin BN, Streisand R, et al.: Psychological issues among children of hereditary breast cancer gene (BRCA1/2) testing participants. Psychooncology 10 (4): 336-46, 2001 Jul-Aug.
147. Wagner TM, Ahner R: Prenatal testing for late-onset diseases such as mutations in the breast cancer gene 1 (BRCA1). Just a choice or a step in the wrong direction? Hum Reprod 13 (5): 1125-6, 1998.
148. Dickens BM, Pei N, Taylor KM: Legal and ethical issues in genetic testing and counseling for susceptibility to breast, ovarian and colon cancer. CMAJ 154 (6): 813-8, 1996.
149. Lodder LN, Frets PG, Trijsburg RW, et al.: Attitudes towards termination of pregnancy in subjects who underwent presymptomatic testing for the BRCA1/BRCA2 gene mutation in The Netherlands. J Med Genet 37 (11): 883-4, 2000.
150. Staton AD, Kurian AW, Cobb K, et al.: Cancer risk reduction and reproductive concerns in female BRCA1/2 mutation carriers. Fam Cancer 7 (2): 179-86, 2008.
151. Tibben A, Frets PG, van de Kamp JJ, et al.: On attitudes and appreciation 6 months after predictive DNA testing for Huntington disease in the Dutch program. Am J Med Genet 48 (2): 103-11, 1993.
152. Adam S, Wiggins S, Whyte P, et al.: Five year study of prenatal testing for Huntington's disease: demand, attitudes, and psychological assessment. J Med Genet 30 (7): 549-56, 1993.
153. Menon U, Harper J, Sharma A, et al.: Views of BRCA gene mutation carriers on preimplantation genetic diagnosis as a reproductive option for hereditary breast and ovarian cancer. Hum Reprod 22 (6): 1573-7, 2007.
154. Struewing JP, Abeliovich D, Peretz T, et al.: The carrier frequency of the BRCA1 185delAG mutation is approximately 1 percent in Ashkenazi Jewish individuals. Nat Genet 11 (2): 198-200, 1995.
155. Rothenberg KH: Breast cancer, the genetic "quick fix," and the Jewish community. Ethical, legal, and social challenges. Health Matrix Clevel 7 (1): 97-124, 1997 Winter.
156. Foster MW, Bernsten D, Carter TH: A model agreement for genetic research in socially identifiable populations. Am J Hum Genet 63 (3): 696-702, 1998.
157. Burhansstipanov L, Bemis LT, Dignan MB: Native American cancer education: genetic and cultural issues. J Cancer Educ 16 (3): 142-5, 2001 Autumn.
158. Hughes C, Fasaye GA, LaSalle VH, et al.: Sociocultural influences on participation in genetic risk assessment and testing among African American women. Patient Educ Couns 51 (2): 107-14, 2003.
159. Julian-Reynier CM, Bouchard LJ, Evans DG, et al.: Women's attitudes toward preventive strategies for hereditary breast or ovarian carcinoma differ from one country to another: differences among English, French, and Canadian women. Cancer 92 (4): 959-68, 2001.
160. Phillips KA, Warner E, Meschino WS, et al.: Perceptions of Ashkenazi Jewish breast cancer patients on genetic testing for mutations in BRCA1 and BRCA2. Clin Genet 57 (5): 376-83, 2000.
161. Freedman TG: Genetic susceptibility testing: ethical and social quandaries. Health Soc Work 23 (3): 214-22, 1998.
162. Parens E: Glad and terrified: on the ethics of BRACA1 and 2 testing. Cancer Invest 14 (4): 405-11, 1996.
163. Winter PR, Wiesner GL, Finnegan J, et al.: Notification of a family history of breast cancer: issues of privacy and confidentiality. Am J Med Genet 66 (1): 1-6, 1996.
164. Statement of the American Society of Clinical Oncology: genetic testing for cancer susceptibility, Adopted on February 20, 1996. J Clin Oncol 14 (5): 1730-6; discussion 1737-40, 1996.
165. Burke W, Daly M, Garber J, et al.: Recommendations for follow-up care of individuals with an inherited predisposition to cancer. II. BRCA1 and BRCA2. Cancer Genetics Studies Consortium. JAMA 277 (12): 997-1003, 1997.
166. Hallowell N, Foster C, Eeles R, et al.: Balancing autonomy and responsibility: the ethics of generating and disclosing genetic information. J Med Ethics 29 (2): 74-9; discussion 80-3, 2003.
167. van Roosmalen MS, Stalmeier PF, Verhoef LC, et al.: Randomized trial of a shared decision-making intervention consisting of trade-offs and individualized treatment information for BRCA1/2 mutation carriers. J Clin Oncol 22 (16): 3293-301, 2004.
168. Tiller K, Meiser B, Gaff C, et al.: A randomized controlled trial of a decision aid for women at increased risk of ovarian cancer. Med Decis Making 26 (4): 360-72, 2006 Jul-Aug.
169. Metcalfe KA, Poll A, O'Connor A, et al.: Development and testing of a decision aid for breast cancer prevention for women with a BRCA1 or BRCA2 mutation. Clin Genet 72 (3): 208-17, 2007.
170. Schwartz MD, Lerman C, Brogan B, et al.: Impact of BRCA1/BRCA2 counseling and testing on newly diagnosed breast cancer patients. J Clin Oncol 22 (10): 1823-9, 2004.
171. Beattie MS, Crawford B, Lin F, et al.: Uptake, time course, and predictors of risk-reducing surgeries in BRCA carriers. Genet Test Mol Biomarkers 13 (1): 51-6, 2009.
172. Phillips KA, Jenkins MA, Lindeman GJ, et al.: Risk-reducing surgery, screening and chemoprevention practices of BRCA1 and BRCA2 mutation carriers: a prospective cohort study. Clin Genet 70 (3): 198-206, 2006.
173. Claes E, Evers-Kiebooms G, Decruyenaere M, et al.: Surveillance behavior and prophylactic surgery after predictive testing for hereditary breast/ovarian cancer. Behav Med 31 (3): 93-105, 2005.
174. Lodder LN, Frets PG, Trijsburg RW, et al.: One year follow-up of women opting for presymptomatic testing for BRCA1 and BRCA2: emotional impact of the test outcome and decisions on risk management (surveillance or prophylactic surgery). Breast Cancer Res Treat 73 (2): 97-112, 2002.
175. Meijers-Heijboer EJ, Verhoog LC, Brekelmans CT, et al.: Presymptomatic DNA testing and prophylactic surgery in families with a BRCA1 or BRCA2 mutation. Lancet 355 (9220): 2015-20, 2000.
176. Metcalfe KA, Foulkes WD, Kim-Sing C, et al.: Family history as a predictor of uptake of cancer preventive procedures by women with a BRCA1 or BRCA2 mutation. Clin Genet 73 (5): 474-9, 2008.
177. Metcalfe KA, Birenbaum-Carmeli D, Lubinski J, et al.: International variation in rates of uptake of preventive options in BRCA1 and BRCA2 mutation carriers. Int J Cancer 122 (9): 2017-22, 2008.
178. Friebel TM, Domchek SM, Neuhausen SL, et al.: Bilateral prophylactic oophorectomy and bilateral prophylactic mastectomy in a prospective cohort of unaffected BRCA1 and BRCA2 mutation carriers. Clin Breast Cancer 7 (11): 875-82, 2007.
179. Tercyak KP, Peshkin BN, Brogan BM, et al.: Quality of life after contralateral prophylactic mastectomy in newly diagnosed high-risk breast cancer patients who underwent BRCA1/2 gene testing. J Clin Oncol 25 (3): 285-91, 2007.
180. Scheuer L, Kauff N, Robson M, et al.: Outcome of preventive surgery and screening for breast and ovarian cancer in BRCA mutation carriers. J Clin Oncol 20 (5): 1260-8, 2002.
181. Botkin JR, Smith KR, Croyle RT, et al.: Genetic testing for a BRCA1 mutation: prophylactic surgery and screening behavior in women 2 years post testing. Am J Med Genet A 118 (3): 201-9, 2003.
182. Uyei A, Peterson SK, Erlichman J, et al.: Association between clinical characteristics and risk-reduction interventions in women who underwent BRCA1 and BRCA2 testing: a single-institution study. Cancer 107 (12): 2745-51, 2006.
183. Schwartz MD, Kaufman E, Peshkin BN, et al.: Bilateral prophylactic oophorectomy and ovarian cancer screening following BRCA1/BRCA2 mutation testing. J Clin Oncol 21 (21): 4034-41, 2003.
184. Madalinska JB, van Beurden M, Bleiker EM, et al.: Predictors of prophylactic bilateral salpingo-oophorectomy compared with gynecologic screening use in BRCA1/2 mutation carriers. J Clin Oncol 25 (3): 301-7, 2007.
185. van Dijk S, van Roosmalen MS, Otten W, et al.: Decision making regarding prophylactic mastectomy: stability of preferences and the impact of anticipated feelings of regret. J Clin Oncol 26 (14): 2358-63, 2008.
186. Ray JA, Loescher LJ, Brewer M: Risk-reduction surgery decisions in high-risk women seen for genetic counseling. J Genet Couns 14 (6): 473-84, 2005.
187. Hallowell N: 'You don't want to lose your ovaries because you think 'I might become a man". Women's perceptions of prophylactic surgery as a cancer risk management option. Psychooncology 7 (3): 263-75, 1998 May-Jun.
188. Schneider KA, Stopfer JE, Peters JA, et al.: Complexities in cancer risk counseling: presentation of three cases. J Genet Couns 6(2): 147-168, 1997.
189. Tarkan L: My Mother's Breast: Daughters Face Their Mothers' Cancer. Dallas, TX: Taylor Publishing, 1999.
190. Stefanek ME, Helzlsouer KJ, Wilcox PM, et al.: Predictors of and satisfaction with bilateral prophylactic mastectomy. Prev Med 24 (4): 412-9, 1995.
191. Graves KD, Peshkin BN, Halbert CH, et al.: Predictors and outcomes of contralateral prophylactic mastectomy among breast cancer survivors. Breast Cancer Res Treat 104 (3): 321-9, 2007.
192. Bresser PJ, Seynaeve C, Van Gool AR, et al.: Satisfaction with prophylactic mastectomy and breast reconstruction in genetically predisposed women. Plast Reconstr Surg 117 (6): 1675-82; discussion 1683-4, 2006.
193. Brandberg Y, Sandelin K, Erikson S, et al.: Psychological reactions, quality of life, and body image after bilateral prophylactic mastectomy in women at high risk for breast cancer: a prospective 1-year follow-up study. J Clin Oncol 26 (24): 3943-9, 2008.
194. Lobb E, Meiser B: Genetic counselling and prophylactic surgery in women from families with hereditary breast or ovarian cancer. Lancet 363 (9424): 1841-2, 2004.
195. Lobb EA, Butow PN, Meiser B, et al.: Tailoring communication in consultations with women from high risk breast cancer families. Br J Cancer 87 (5): 502-8, 2002.
196. Lobb EA, Butow PN, Barratt A, et al.: Communication and information-giving in high-risk breast cancer consultations: influence on patient outcomes. Br J Cancer 90 (2): 321-7, 2004.
197. Kauff ND, Satagopan JM, Robson ME, et al.: Risk-reducing salpingo-oophorectomy in women with a BRCA1 or BRCA2 mutation. N Engl J Med 346 (21): 1609-15, 2002.
198. Schmeler KM, Sun CC, Bodurka DC, et al.: Prophylactic bilateral salpingo-oophorectomy compared with surveillance in women with BRCA mutations. Obstet Gynecol 108 (3 Pt 1): 515-20, 2006.
199. MacDonald DJ, Sarna L, Uman GC, et al.: Cancer screening and risk-reducing behaviors of women seeking genetic cancer risk assessment for breast and ovarian cancers. Oncol Nurs Forum 33 (2): E27-35, 2006.
200. Litton JK, Westin SN, Ready K, et al.: Perception of screening and risk reduction surgeries in patients tested for a BRCA deleterious mutation. Cancer 115 (8): 1598-604, 2009.
201. Tyndel S, Austoker J, Henderson BJ, et al.: What is the psychological impact of mammographic screening on younger women with a family history of breast cancer? Findings from a prospective cohort study by the PIMMS Management Group. J Clin Oncol 25 (25): 3823-30, 2007.
202. Rees G, Young MA, Gaff C, et al.: A qualitative study of health professionals' views regarding provision of information about health-protective behaviors during genetic consultation for breast cancer. J Genet Couns 15 (2): 95-104, 2006.
203. Bresser PJ, Seynaeve C, Van Gool AR, et al.: The course of distress in women at increased risk of breast and ovarian cancer due to an (identified) genetic susceptibility who opt for prophylactic mastectomy and/or salpingo-oophorectomy. Eur J Cancer 43 (1): 95-103, 2007.
204. Frost MH, Schaid DJ, Sellers TA, et al.: Long-term satisfaction and psychological and social function following bilateral prophylactic mastectomy. JAMA 284 (3): 319-24, 2000.
205. Metcalfe KA, Esplen MJ, Goel V, et al.: Psychosocial functioning in women who have undergone bilateral prophylactic mastectomy. Psychooncology 13 (1): 14-25, 2004.
206. Weitzel JN, McCaffrey SM, Nedelcu R, et al.: Effect of genetic cancer risk assessment on surgical decisions at breast cancer diagnosis. Arch Surg 138 (12): 1323-8; discussion 1329, 2003.
207. Schlich-Bakker KJ, Ausems MG, Schipper M, et al.: BRCA1/2 mutation testing in breast cancer patients: a prospective study of the long-term psychological impact of approach during adjuvant radiotherapy. Breast Cancer Res Treat 109 (3): 507-14, 2008.
208. Frost MH, Slezak JM, Tran NV, et al.: Satisfaction after contralateral prophylactic mastectomy: the significance of mastectomy type, reconstructive complications, and body appearance. J Clin Oncol 23 (31): 7849-56, 2005.
209. Schwartz MD: Contralateral prophylactic mastectomy: efficacy, satisfaction, and regret. J Clin Oncol 23 (31): 7777-9, 2005.
210. Geiger AM, Nekhlyudov L, Herrinton LJ, et al.: Quality of life after bilateral prophylactic mastectomy. Ann Surg Oncol 14 (2): 686-94, 2007.
211. Isern AE, Tengrup I, Loman N, et al.: Aesthetic outcome, patient satisfaction, and health-related quality of life in women at high risk undergoing prophylactic mastectomy and immediate breast reconstruction. J Plast Reconstr Aesthet Surg 61 (10): 1177-87, 2008.
212. Kenen RH, Shapiro PJ, Hantsoo L, et al.: Women with BRCA1 or BRCA2 mutations renegotiating a post-prophylactic mastectomy identity: self-image and self-disclosure. J Genet Couns 16 (6): 789-98, 2007.
213. Altschuler A, Nekhlyudov L, Rolnick SJ, et al.: Positive, negative, and disparate--women's differing long-term psychosocial experiences of bilateral or contralateral prophylactic mastectomy. Breast J 14 (1): 25-32, 2008 Jan-Feb.
214. Patenaude AF, Orozco S, Li X, et al.: Support needs and acceptability of psychological and peer consultation: attitudes of 108 women who had undergone or were considering prophylactic mastectomy. Psychooncology 17 (8): 831-43, 2008.
215. Elit L, Esplen MJ, Butler K, et al.: Quality of life and psychosexual adjustment after prophylactic oophorectomy for a family history of ovarian cancer. Fam Cancer 1 (3-4): 149-56, 2001.
216. Robson M, Hensley M, Barakat R, et al.: Quality of life in women at risk for ovarian cancer who have undergone risk-reducing oophorectomy. Gynecol Oncol 89 (2): 281-7, 2003.
217. Finch A, Metcalfe K, Lui J, et al.: Breast and ovarian cancer risk perception after prophylactic salpingo-oophorectomy due to an inherited mutation in the BRCA1 or BRCA2 gene. Clin Genet 75 (3): 220-4, 2009.
218. Madalinska JB, Hollenstein J, Bleiker E, et al.: Quality-of-life effects of prophylactic salpingo-oophorectomy versus gynecologic screening among women at increased risk of hereditary ovarian cancer. J Clin Oncol 23 (28): 6890-8, 2005.
219. Massie MJ, Muskin PR, Stewart DE: Psychotherapy with a woman at high risk for developing breast cancer. Gen Hosp Psychiatry 20 (3): 189-97, 1998.
220. Shoda Y, Mischel W, Miller SM, et al.: Psychological interventions and genetic testing: facilitating informed decisions about BRCA1/2 cancer susceptibility. J Clin Psychol Med Settings 5(1): 3-17, 1998.
221. Halbert CH, Wenzel L, Lerman C, et al.: Predictors of participation in psychosocial telephone counseling following genetic testing for BRCA1 and BRCA2 mutations. Cancer Epidemiol Biomarkers Prev 13 (5): 875-81, 2004.
222. Karp J, Brown KL, Sullivan MD, et al.: The prophylactic mastectomy dilemma: a support group for women at high genetic risk for breast cancer. J Genet Counsel 8 (3): 163-73, 1999.
223. Miller SM, Fleisher L, Roussi P, et al.: Facilitating informed decision making about breast cancer risk and genetic counseling among women calling the NCI's Cancer Information Service. J Health Commun 10 (Suppl 1): 119-36, 2005.
224. Isaacs C, Peshkin BN, Schwartz M, et al.: Breast and ovarian cancer screening practices in healthy women with a strong family history of breast or ovarian cancer. Breast Cancer Res Treat 71 (2): 103-12, 2002.
225. Peshkin BN, Schwartz MD, Isaacs C, et al.: Utilization of breast cancer screening in a clinically based sample of women after BRCA1/2 testing. Cancer Epidemiol Biomarkers Prev 11 (10 Pt 1): 1115-8, 2002.
226. Tinley ST, Houfek J, Watson P, et al.: Screening adherence in BRCA1/2 families is associated with primary physicians' behavior. Am J Med Genet A 125 (1): 5-11, 2004.
227. Lerman C, Seay J, Balshem A, et al.: Interest in genetic testing among first-degree relatives of breast cancer patients. Am J Med Genet 57 (3): 385-92, 1995.
228. Watson M, Kash KM, Homewood J, et al.: Does genetic counseling have any impact on management of breast cancer risk? Genet Test 9 (2): 167-74, 2005.

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