Locoregional recurrence in skin-sparing and nipple-sparing mastectomies

Background Skin- and nipple-sparing mastectomies (SSMs/NSMs) present as an alternative for patients requiring mastectomy, with better aesthetic results. We aimed to evaluate the locoregional recurrence (LRR) rate and its predictive factors. Methods Retrospective analysis of all consecutive cases of SSM and NSM for a primary diagnosis of in situ or invasive breast cancer, at a national cancer center, from January 1st, 2013 to May 31st, 2019. The primary outcome was LRR. Secondary outcomes included LRR predictive factors, overall survival (OS), and disease-free survival (DFS). Results There were included 461 patients; 402 (87%) with invasive carcinoma. The median age was 46 (interquartile range [IQR]: 40-53) years. Ninety (20%) patients had locally advanced disease. LRR rate was 3.0%, with a median follow-up time of 39 (IQR: 21-59) months. The median time to recurrence was 22 (IQR: 10-45) months. Factors independently associated with LRR were high histological grade, negative estrogen receptor status, and high Ki67 (p < 0.05). OS was 94.8% and DFS was 92.8%. LRR was associated with decreased OS. Discussion SSM and NSM present as a safe approach to breast cancer requiring mastectomy, including selected patients with a locally advanced tumor. The associated LRR rate is 3.0%, with risk factors being high grade, negative estrogen receptor status, and high Ki67.