A retrospective comparison of clinical outcomes between endoscopic and open nipple-sparing mastectomy with immediate implant reconstruction versus breast-conserving surgery.

OBJECTIVES: To compare perioperative outcomes, complications, aesthetic results, and patient-reported satisfaction among breast-conserving surgery (BCS), endoscopic nipple-sparing (ENS) mastectomy with immediate implant-based reconstruction, and open nipple-sparing (ONS) mastectomy, and to identify factors independently associated with aesthetic outcome. METHODS: This retrospective study included 160 early-stage breast cancer patients (BCS=100, ENS=30, ONS=30). Perioperative outcomes, complications classified according to the Clavien-Dindo system, oncologic safety, aesthetic scores, and BREAST-Q domains were analyzed. Multivariable regression analysis was performed to identify predictors of aesthetic outcomes. A 1:1 propensity score-matched sensitivity analysis (30 pairs) was conducted, which confirmed significantly reduced blood loss in the ENS group (P<0.001), and showed a numerical but non-significant difference in aesthetic scores (P=0.088). RESULTS: The ENS group had the longest operative time (159.2 min), whereas the ONS group experienced the greatest intraoperative blood loss (72.5 ml). Patients in the BCS group had the shortest drainage and hospital stay (both P<0.001). The overall complication rates were 7.0% in BCS group, 20.0% in the ENS group, and 16.7% in the ONS group. Aesthetic scores were highest in the BCS group (84.9), followed by the ENS group (79.2) and the ONS group (75.8) (all P<0.001). BREAST-Q scores demonstrated a similar pattern. No significant differences were observed among groups regarding margin positivity or short-term recurrence. Multivariable analysis identified surgical approach, complications, and tumor location as independent predictors of aesthetic outcomes. CONCLUSION: BCS remains the preferred option for eligible patients with early-stage breast cancer. For patients unsuited to BCS, ENS is associated with significantly lower intraoperative blood loss than ONS. While aesthetic scores showed a favorable trend in the ENS group, this difference did not reach statistical significance in the propensity score-matched analysis.