Oncologic Safety of Nipple-Sparing Mastectomy for Breast Cancer in BRCA Gene Mutation Carriers: Outcomes at 70 Months Median Follow-Up

Background: Retention of the nipple–areola complex with nipple-sparing mastectomy (NSM) techniques provides a more natural cosmetic result than procedures that sacrifice the nipple. While the oncologic safety of NSM is established by several studies, there is little long-term data on outcomes in BRCA mutation carriers with breast cancer. Patients and Methods: BRCA1/2 mutation carriers who underwent NSM and immediate reconstruction from 2008 to 2019 were reviewed and patients with breast cancer on biopsy or final pathology were included. Patient demographics and tumor characteristics, as well as treatment, recurrence, and survival data were collected. Results: A total of 114 therapeutic NSM were performed in 105 BRCA mutation carriers (56 BRCA1, 47 BRCA2, and two women with both mutations). Median age was 45 years. Cancers were 18% stage 0, 52% stage I, 27% stage II, and 3% stage III. Mean invasive tumor size was 1.6 cm and 33 (35%) invasive tumors were triple negative. There were five (4.4%) positive nipple margins on final pathology; all underwent nipple excision. Most patients (80, 76%) received systemic therapy: 65 (62%) received chemotherapy and 48 (46%) received endocrine therapy. At 70 months median follow-up (range 15–150 months), no patient had developed a recurrence in the retained nipple–areola complex or at the site of a nipple excised for a positive margin. The rate of locoregional recurrence outside the nipple was 2.6%, and the rate of distant recurrence was 3.8%. Overall survival was 96%. Conclusions: NSM is a safe option for BRCA1 and BRCA2 mutation carriers who undergo mastectomy for breast cancer.