Surgical and oncologic outcomes of nipple-sparing mastectomy for a cohort of breast cancer patients including cases with high-risk features

ABSTRACT Background Nipple-sparing mastectomy(NSM) remains controversial in high-risk breast cancer patients. The objective of this study is to assess surgical and oncologic outcomes of NSM and to evaluate association of outcomes with high-risk features. Methods A retrospective review of all NSM cases performed for breast cancer at two academic cancer centers between January 2013-August 2018 was conducted. Results Of 175 NSM, 13(7.4%) were for locally advanced breast cancer(LABC), 52(29.2%) were following neoadjuvant chemotherapy, 21(12.0%) had previous radiation, 40(22.8%) received post-mastectomy radiation, 27(15.4%) had deepithelialized skin-reduction and 13(7.4%) had free nipple-grafting. Median follow-up was 24 months. Nipple necrosis [4(2.2%) cases] was associated with previous radiation(9.5%, p=0.018), skin-reduction(11.1%, p=0.001), and nipple-grafting(15.4%, p=0.001). The nipple-areolar complex margin(NAC) was involved with invasive disease in 1 case. Local recurrence occurred in 8(4.6%) cases, with 1 in-NAC recurrence. Overall survival was 98.3% and disease-free survival(DFS) was 88.6%. LABC was associated with worse DFS (HR 4.28, p=0.011), with all 4 recurrences being distant. Conclusion Previous radiation, skin-reduction and nipple-grafting are associated with increased risk of NAC necrosis. None should be considered absolute contraindications, but patients should be counseled appropriately. While LABC is associated with worse DFS, relapses are systemic. Longer follow-up is needed to establish oncological safety in unselected breast cancer patients.