The lifetime risk of breast cancer for women with deleterious BRCA1 mutations is 40% to 80% and the risk is slightly lower for BRCA2 carriers.

Mastectomy is the most effective prophylactic surgical measure to prevent the development of breast cancer; it reduces a woman’s risk by approximately 90% because a small amount of breast tissue must remain on the skin flaps for viability.

Women with BRCA1 mutations also have an approximate 40% lifetime risk of developing ovarian cancer, and bilateral salpingo-oophorectomy is recommended for prophylaxis.

Removal of the fallopian tubes with the ovaries is recommended because the risk of fallopian tube cancers is slightly higher for mutation carriers.

Oophorectomy does not completely eliminate the risk of abdominal epithelial cancers that behave like and are nearly indistinguishable from ovarian cancer.

In BRCA mutation carriers, there is a greater risk of primary peritoneal carcinoma, which behaves and is treated like ovarian cancer.

The patient should have bilaterial salpingo-oophorectomy once she has had her children or by age 40 years if she has not had children.

It is not recommended to wait until age 60 years to have this procedure, as ovarian cancer usually develops at a younger age.

The National Comprehensive Cancer Network (NCCN) recommendations for use of breast MRI for women with hereditary breast and ovarian cancer syndrome are annual screening with mammography, and breast MRI at alternating 6-month intervals.

MRI is not a substitute for mammography, however, as the modalities are complementary in BRCA-positive mutation carriers.

References:

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. 2007;25:3705-3711.

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. 1999;340:77-84.

Hemel D, Domcheck SM. Breast cancer predisposition syndromes. Hematol Oncol Clin North Am. 2010;24:799-814.

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. 2008;26:1331-1337.

National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology Genetic/Familial High-Risk Assessment: Breast and Ovarian. Available at http://www.nccn.org.