The prevalence of BRCA1 or BRCA 2 mutations is estimated at about 0.2%-0.33% of the population, but these mutations account for 5%-10% of breast cancers and 10%-15% of ovarian cancers among white women in the United States. Lifetime risks may be as high as 85% for breast cancer and 26% for ovarian cancer for affected women. Preventive options for these women include prophylactic surgery, chemoprevention, and regular screening.
A recent observational study assessed the efficacy of prophylactic salpingo-oophorectomy to reduce the risks of breast and ovarian cancer. In a cohort of 2,482 women with BRCA mutations identified from 1974-2008 (followed for 6 months to 27 years), 40% had prophylactic salpingo-oophorectomies. In an analysis of the entire cohort, oophorectomy was associated with significant reductions in all-cause mortality (3.1% vs. 9.8%), ovarian cancer-specific mortality (0.4% vs. 2.5%), and breast cancer-specific mortality (2.1% vs. 5.7%) (level 2 [mid-level] evidence). Among women with no previous breast cancer, oophorectomy was associated with significantly reduced incidence of ovarian cancer (1.3% vs. 5.8%) and breast cancer (11.6% vs. 21.6%). In women with previous breast cancer, oophorectomy was associated with reductions in all-cause mortality (4.2% vs. 16%) and incidence of ovarian cancer (1% vs. 6%) (JAMA 2010 Sep 1;304(9):967).
A new statement from the Society of Gynecologic Oncologists Clinical Practice Committee recommends bilateral salpingo-oophorectomy for women at high risk of ovarian cancer based on family history and presence of BRCA 1 or BRCA 2 mutations after childbearing is complete (Obstet Gynecol 2010 Sep;116(3):733).
For more information, see the BRCA mutation testing and management topic in DynaMed.