Breast Cancer after Prophylactic Bilateral Mastectomy in Women with a BRCA1 or BRCA2 Mutation

This investigation strengthens the case for mastectomy in women with a mutation of the BRCA1 or BRCA2 gene. The identification of the breast-cancer–susceptibility genes BRCA1 1 and BRCA2 2 evoked widespread interest in genetic testing among women at risk for a mutation in these genes. 3 , 4 We found that 57 percent of women without breast cancer who had a 50 percent chance of carrying a BRCA1 or BRCA2 mutation requested genetic testing. 4 This result indicates the need to determine the efficacy of the various options for reducing the risk of breast cancer and for early detection in women with a BRCA1 or BRCA2 mutation. Women with a BRCA1 or BRCA2 mutation have a cumulative lifetime risk of invasive breast cancer . . .