Factors associated with alteration of nipple or skin sensation and impact of duration of time following nipple-sparing mastectomy (NSM): an analysis of 460 cases with comparison of conventional versus endoscopic- or robotic-assisted NSM

The current study aims to evaluate the nipple and skin sensation following nipple-sparing mastectomy (NSM) and identify patient-, surgical-, or treatment-related factors affecting nipple or skin sensation in this cohort. Patients who received NSM with postoperative nipple and skin sensation test evaluation at a single institution over the past 10 years were retrospectively retrieved from a prospectively collected breast cancer surgery database. A total of 460 NSM procedures were included in this current study, with the mean age of 48.3 ± 9.1. Three-hundred eighty-three (83.3%) patients had breast reconstructions. One-hundred seventy-four (37.8%) received conventional NSM (C-NSM), 195 (42.4%) endoscopic-assisted NSM (E-NSM), and 91 (19.8%) robotic-assisted NSM (R-NSM) procedures. For nipple sensation assessment, 15 (3.3%) were grade 0, 83 (18.2%) grade I, 229 (49.7%) grade II, and 133 (28.9%) grade III (normal sensation), respectively, with mean grade score of 2.1 ± 0.7. The preserved (grade III) nipple sensation rate was 36.2% (63/174) in the C-NSM group, 26.7% (52/195) in the E-NSM group, and 19.7% (18/91) in the R-NSM group (P = 0.06). The "time since surgery to last evaluation" was significantly longer in the C-NSM group (45.6 ± 34 months) or E-NSM group (44.7 ± 35.8 months) as compared to R-NSM group (31.8 ± 16 months, P 60 months vs. ≦ 12 months: nipple odds ratio (OR) = 5.75, P