Predictors that influence contralateral prophylactic mastectomy election among women with ductal carcinoma in situ who tested negative for a BRCA mutation.

Abstract

42 Background: Patients with ductal carcinoma in situ (DCIS) are at increased risk for developing contralateral breast cancer (CBC). Consequently, more women with DCIS are electing to undergo contralateral prophylactic mastectomy (CPM). We previously reported a 27% CPM rate among patients with DCIS who were evaluated for BRCA genetic testing (positive, negative, not tested). In this specific cohort, we further evaluated factors associated with CPM in patients with DCIS who tested negative for a BRCA mutation. Specifically, we aimed to identify differences within BRCA-negative patients who underwent CPM and those who did not. Methods: This retrospective study from a prospective registry included 100 women with DCIS referred for genetic counseling between 2003 and 2011. Patient characteristics included: age, marital and educational status, tumor markers, nuclear grade, family history of breast cancer (BC) and ovarian cancer (OC), race, Ashkenazi Jewish ancestry, and BRCA results. Univariate and multivariate logistic regression analyses were used to determine predictive factors associated with CPM election. Results: Of 100 BRCA-negative patients, 31 (31%) underwent CPM. Univariate analysis revealed patients who had a first-degree relative with OC were more likely to elect CPM that those who did not (p = 0.0278). Patients who had a family history of OC (53.3%) were more likely to choose CPM than those with no family history (p = 0.0425). Married patients were more likely to elect CPM than those who were not married (p = 0.0235). In multivariate analysis, married patients were more likely to elect CPM than those who were not married (OR = 4.367; 95% CI, 1.198-15.924; p = 0.0255). Conclusions: The CPM rate among patients with DCIS who tested negative for a BRCA mutation is high. Factors associated with increased rate of CPM among this group include a family history of OC and being married. Further studies are needed to evaluate patients' perceptions of CBC risk and their role in the likelihood of CPM choice.