Abstract
Background. At present,the indication for nipple-sparing mastectomy（NSM）remains inconclusive,and the occult NAC involvement （NI）is one of the most considerable problem when carrying out NSM.We aimed at identifying the predictive factors of NAC involvement,to provide an implement of selecting suitable NSM candidates.Methods. The association between the NI and tumorous clinicopathologic characteristics of 272 mastectomies and 31 therapeutic NSM performed in our hospital from 2016 to 2018，were retrospectively evaluated.Results.38 of 272（14.0%）mastectomies and 2 of 31（6.5%）NSM were confirmed to have NAC involvement, and all the intraoperative frozen section examination of the sub-areolar/nipple tissue were consistent with the permanent section examination in NSM. The median follow-up durations for NSM was 24 months,local recurrence occurred in 1 of 30（3.2%） patients.Among 272 mastectomies，the NAC involvement showed significant association with the abnormal nipple signs（P＜0.001），tumor size ＞4cm measured by ultrasound （P＜0.001）and gross pathologic samples（P＜0.001），tumor-nipple distance ＜1cm（P=0.003），central location（P＜0.001），lymph node metastasis（P=0.004），and HER2 overexpression（P=0.023）.A preoperative predictive model of NAC involvement utilizing nipple signs(normal or abnormal),tumor size(≤4cm or ＞4cm),tumor location(central or peripheral) showed a PPV of 85.7% and a NPV of 90.3%.Conclusions.The local recurrence rate after NSM is low （3.2%）in our study，and the intraoperative frozen section examination plays an important role in the procedure of NSM.Further more，we proposed a predictive model of the NAC involvement utilizing the preoperative tumorous characteristics，including the nipple signs，tumor size measured by ultrasound，and the tumor location.This predictive model could be working in the planning of breast cancer surgery.
Correction to: Neurovascular structure-adjacent frozen-section examination robotic-assisted radical prostatectomy: outcomes from 500 consecutive cases in the UK
