Single-Stage excision and sentinel lymph node biopsy in selected patients with cutaneous melanoma: a monocentric...

Standard surgery for invasive cutaneous melanoma involves diagnostic excision followed by wide local excision (WLE) and sentinel lymph node biopsy (SLNB), when indicated. In anatomically critical sites requiring complex reconstruction, a Single-Stage strategy combining WLE and SLNB may preserve native lymphatic drainage and reduce repeated procedures. We compared its long-term oncologic outcomes with conventional Two-Stage surgery. This retrospective, single-center cohort included 825 patients treated during 2013-2022: 49 underwent Single-Stage surgery for lesions highly suspicious for invasive melanoma on dermoscopy and reflectance confocal microscopy and requiring complex reconstruction, and 776 underwent Two-Stage surgery. Follow-up continued through December 2024. Recurrence-free survival (RFS) was assessed using Kaplan-Meier estimates, log-rank tests, and unadjusted Cox models; analyses by tumor thickness were exploratory. Single-Stage patients were older; median follow-up was approximately 50 months in both groups. All final margins were negative. Five-year RFS was 91.9% versus 79.4% for Single-Stage versus Two-Stage surgery (log-rank P = 0.037; unadjusted hazard ratio = 0.391; 95% confidence interval = 0.157-0.974). Corresponding estimates were 86.8% versus 64.7% for melanomas >2.0 mm thick (log-rank P = 0.038) and 100.0% versus 95.8% for melanomas ≤2.0 mm thick (log-rank P = 0.390). Disease-free status at the last assessment did not differ significantly overall or within either thickness stratum. Single-Stage surgery was feasible and showed a nominally significant association with higher RFS. These hypothesis-generating findings support Single-Stage surgery as a promising option for selected patients and warrant prospective multicenter validation.