Cohort study of surgical outcomes after risk-reducing mastectomy among BRCA1 and BRCA2 germline pathogenic variant carriers

A nationwide cohort study in Sweden analyzed cancer risk and surgical complications after risk-reducing mastectomy (RRM) among women with germline pathogenic variants (gPVs) in BRCA1 or BRCA2. A total of 1208 women with a confirmed gPV in BRCA1 or BRCA2 without previous breast cancer were identified between March 31, 1994 January 2, 2019 and followed to December 31, 2023. In the RRM group (507 women, median age at RRM 39.7 years; range 19.6-72.1), one woman developed breast cancer (incidence 2 cases per 10,000 person-years). In the no RRM group (701 women, median age at genetic testing 50.6 years; range 4.3-93.6), 112 women developed breast cancer (162 per 10,000 person-years). At RRM, 17 or 507 women (3.4%) received a diagnosis of occult breast cancer. Early major surgical postoperative complications associated with reoperation occurred in19 of 507 women (3.7%). The authors conclude that the risk of developing breast cancer after RRM was low.