Differences Among a Modern Cohort of BRCA Mutation Carriers Choosing Bilateral Prophylactic Mastectomies Compared to Breast Surveillance.

Abstract

Women with a BRCA mutation have significantly elevated breast cancer risk, which can be reduced by >90% with bilateral prophylactic mastectomy (BPM). We sought to compare a cohort of BRCA mutation carriers choosing BPM versus breast surveillance to better elucidate factors that may impact decision making. Women with a BRCA mutation were retrospectively identified from a prospectively maintained database. The surveillance cohort (n = 313) consisted of women seen in a high-risk clinic between 2014 and 2016, while the surgery cohort (n = 142) consisted of women who underwent BPM between 2010 and 2016. Clinical and familial factors were compared between the groups. Women choosing BPM were more likely to have a BRCA1 than BRCA2 mutation compared with the surveillance group (57 vs. 45%, p = 0.02) and were less likely to have a personal history of ovarian cancer (10 vs. 20%, p = 0.01). Furthermore, women undergoing BPM were more likely to be married (78 vs. 62%, p = 0.01), to have more children (median 2 vs. 1, p < 0.001), and to have undergone a prophylactic oophorectomy (61 vs. 37%, p < 0.001). Women choosing BPM had more first-degree relatives (63 vs. 48%, p = 0.01) or a sister (23 vs. 14%, p = 0.02) with a history of breast cancer and were more likely to have a family member with ovarian cancer under the age of 40 years (9 vs. 4%, p = 0.03). There was no difference in the number of prior breast biopsies or history of atypia/lobular carcinoma in situ. The decision to undergo BPM appears multifactorial, with gene mutation, family history, and relationships appearing to have the strongest influence on decision making.