60 Nipple-Sparing Mastectomy in Patients With BRCA and Other Breast Cancer–Related Gene Mutations

60 Nipple-Sparing Mastectomy in Patients With BRCA and Other Breast Cancer–Related Gene Mutations

Background

Nipple-sparing mastectomy (NSM) and genetic panel testing have become more common in breast care. Our study aims to evaluate the outcomes of patients with BRCA and other breast cancer–related gene mutations who have undergone NSM.

Materials and Methods

We conducted an institutional review board–approved chart review of patients with breast cancer–related gene mutations identified in a database of patients with NSM performed from 2007 to 2017 in a community hospital. Clinical and pathological data were collected and analyzed.

Results

Among the 271 patients in the NSM database, 226 (83%) underwent genetic testing, of which 102 (45%) had only BRCA testing and 124 (55%) had panel testing. Fifty-eight patients (26%) tested positive for a genetic mutation, of which 53 patients (24%) were identified with a breast cancer–related gene mutation. These mutations were BRCA1 in 22 patients (42%), BRCA2 in 22 patients (42%), ATM in 3 patients (6%), PALB2 in 3 patients (6%), CHEK2 in 3 patients (6%), and CDH1 in 1 patient (2%). Among those patients, one had both BRCA2 and CHEK2 mutations.

The purpose of the NSM was for only risk reduction in 40 patients (76%), combined treatment and risk reduction in 12 patients (23%), and only treatment in 1 patient (2%). All patients underwent immediate reconstruction, with direct implant reconstruction being the most common in 29 patients (55%), followed by autologous tissue flaps in 13 patients (25%), and tissue expanders in 11 patients (21%). Nine patients (17%) had invasive ductal carcinoma (IDC) and 5 patients (9%) had ductal carcinoma in situ (DCIS). Three patients had chemotherapy only, 1 patient had endocrine therapy only, 3 patients had both chemotherapy and endocrine therapy, and 2 patients had chemotherapy, post-mastectomy radiation, and endocrine therapy. There were no incidental cancers identified in prophylactic NSM.

The median follow-up period was 116 months (range, 0-197). No breast cancers developed on the side of the prophylactic NSM. No local recurrence was observed. There was 1 regional and 1 distant recurrence. One patient with a BRCA1 mutation had undergone neoadjuvant chemotherapy, a therapeutic NSM for a triple-negative IDC with a negative sentinel node biopsy and a complete pathologic response, and a contralateral risk-reducing NSM; she developed an axillary recurrence on the therapeutic side. One patient with a BRCA2 mutation with a prior right-modified radical mastectomy for a triple-negative invasive cancer later underwent a prophylactic NSM; she developed bone metastasis. There were no mortalities in the follow-up period.

Conclusion

Our study suggests that NSM is a safe surgical approach for patients with BRCA and other breast cancer–related gene mutations. Further studies are needed to support these findings.