Preventive surgeries benefit women with breast cancer gene mutations

Among women with BRCA1 or BRCA2 mutations, prophylactic mastectomy and salpingo-oophorectomy reduce the high risks for breast and ovarian cancer, and the latter procedure improves survival, according to results from one of the largest prospective studies on the topic to date. Researchers also found that benefit was conferred whether the mutation was located on the BRCA1 or BRCA2 gene and whether the women had previously had cancer.

Researchers analyzed data from 2,482 women with BRCA1 or BRCA2 mutations from 22 clinical and research genetics centers in Europe and North America.

During 3 years of prospective follow-up, no breast cancers were diagnosed among the 247 women who chose prophylactic mastectomy, whereas 98 (7%) of the 1,372 women who did not choose prophylactic surgery were diagnosed with breast cancer during a similar follow-up period. Prophylactic mastectomy did not seem to affect overall survival, however.

Among women with a previous breast cancer diagnosis, the HR for ovarian cancer among BRCA1 mutation carriers was 0.15 (95% CI, 0.04-0.63). The researchers diagnosed no cases of ovarian cancer in BRCA2 mutation carriers after preventive salpingo-oophorectomy. The preventive surgery also lowered the risk for first breast cancer diagnosis in both BRCA1 and BRCA2 mutation carriers and lowered the rates of all-cause mortality, breast cancer-specific mortality, and ovarian cancer-specific mortality.

Domchek SM, Friebel TM, Singer CF, et al. Association of risk-reducing surgery in BRCA1 or BRCA2 mutation carriers with cancer risk and mortality. JAMA. 2010;304(9):967-975.