A novel technique of reverse-sequence endoscopic nipple-sparing mastectomy with direct-to-implant breast reconstruction: medium-term oncological safety outcomes and feasibility of 24-hour discharge for breast cancer patients

Background: Due to the short operation time and no need for special instruments, reverse-sequence endoscopic nipple-sparing mastectomy (R-E-NSM) with direct-to-implant breast reconstruction (DIBR) has been rapidly becoming popular in the last three years. However, there has yet to be an evaluation of its oncologic safety or the feasibility of discharging patients within 24 hours. Materials and Methods: In this single-center retrospective cohort study, individuals diagnosed with stage 0–III breast cancer between May 2020 and April 2022 who underwent traditional open mastectomy or R-E-NSM with DIBR were included. Follow-up started on the date of surgery and ended in December 2023. Data, including demographics, tumor characteristics, medium-term oncological outcomes, and postoperative complications, were collected and analyzed. Propensity score matching (PSM) was performed to minimize selection bias. Results: This study included 1679 patients (median IQR age, 50 44-57 years). Of these, 344 patients underwent R-E-NSM with DIBR (RE-R group), and 1335 patients underwent traditional open mastectomy (TOM group). The median IQR follow-up time was 30 24-36 months (29 23-33 months in the RE-R group and 30 24-36 months in the TOM group). Regarding before or after PSM, the P value of local recurrence-free survival (LRFS, 0.910 and 0.450), regional recurrence-free survival (RRFS, 0.780 and 0.620), distant metastasis-free survival (DMFS, 0.061 and 0.130), overall survival (OS, 0.260 and 0.620), disease-free survival (DFS, 0.120 and 0.330) were not significantly different between the RE-R group and the TOM group. The 3y-LRFS and 3y-DFS rates were 99.0% and 97.1% for the RE-R group and 99.5% and 95.3% for the TOM group, respectively. The rates of any complications and major complications were not significantly different between the RE-R patients who were discharged within 24 hours and the RE-R patients who were not discharged within 24 hours ( P =0.290, P =0.665, respectively) or the TOM patients who were discharged within 24 hours ( P =0.133, P =0.136, respectively). Conclusions: R-E-NSM with DIBR is an innovative oncologic surgical procedure that not only improves cosmetic outcomes but also ensures reliable oncologic safety and fewer complications, enabling patients to be safely discharged within 24 hours. A long-term prospective multicenter assessment will be supporting.