Nipple-sparing mastectomy (NSM), which preserved the nipple areolar complex (NAC) and skin flap during mastectomy, was increasingly performed in breast cancer patients due to better cosmetic outcome, higher patient satisfaction, and maintained oncologic safety. Minimal invasive surgery had become the main stream of operations, and new surgical innovations of NSM, like endoscopic nipple sparing mastectomy (E-NSM) or robotic nipple sparing mastectomy (R-NSM), were emerging and applied in the surgical treatment of breast cancer. E-NSM, which is performed through small axillary and/or peri-areolar incisions, was reported to be associated with small inconspicuous incision and good cosmetic outcome. Conventional E-NSM was performed with two separate incisions over axilla and peri-areolar regions. E-NSM with areolar incision, just like NSM with areolar related incision (NAC ischemia/necrosis rate: range 7%-81.8%), was associated with increased NAC ischemia/necrosis (reported ranged: 9.1-19%). New technique modifications of E-NSM were emerging focusing on single axillary incision NSM, which spare the peri-areolar incision and thereby decrease the compromise of bloody supply from mastectomy skin flap, was reported to have low NAC necrosis rate (0%). However, the 2-dimensional endoscopic in-line camera produces an inconsistent optical window around the curvature of the breast skin flap, and the internal mobility was limited and the dissection angles were inadequate with traditional endoscopic rigid tips instruments through single access. Due to the limitations of endoscopy instruments and technique difficulty, neither conventional E-NSM nor single access E-NSM was widespread used in breast cancer R-NSM, which introduce da Vinci surgical platform through a small extramammary axillary or lateral chest wound to perform NSM, had been applied in the surgical treatment of early breast cancer or risk reducing mastectomy. R-NSM, which incorporated 3- dimensional (3D) imaging system and flexibility of robotic arm and instruments, was reported to have the potential to overcome the technique difficulty of E-NSM. The preliminary results of R-NSM from current literature reported series and ours were safe, and associated with good cosmetic outcome and high patients' satisfaction. However, evidence comparing R-NSM to conventional NSM (CNSM) or E-NSM was lacking. In this study, the authors aim to investigate and analyze the clinical and aesthetic outcomes as well as the cost effectiveness of R-NSM through a longitudinal cohort study design whereby a retrospective review will be carried out for patients undergoing R-NSM, E-NSM or C-NSM. Multi-centers pooled data analysis would be performed for comparisons of R-NSM compared with C-NSM or E-NSM.
This study will retrospectively collect and evaluate the surgical outcomes of robotic nipple sparing mastectomy (R-NSM) compared with endoscopic assisted NSM (E-NSM) or conventional NSM (C-NSM) in the management of breast cancer. Multi-centers pooled data analysis would be performed for comparisons of R-NSM compared with C-NSM or E-NSM.