Surgical complications after therapeutic lymph node dissection in stage III–IV melanoma: impact of neoadjuvant immunotherapy

INTRODUCTION: Neoadjuvant immune checkpoint inhibitors (ICI) have recently entered clinical practice in management of melanoma, yet its impact on surgical outcomes remains unclear. This study evaluated the influence of neoadjuvant ICI on postoperative complications, surgical metrics, adjuvant treatment delay and survival in patients with stage III-IV melanoma following therapeutic lymph node dissections. MATERIAL AND METHODS: This retrospective cohort included patients that underwent surgery for nodal recurrence between 2019 and 2024. Patient characteristics, adverse events of ICI, surgical metrics, postoperative complications, postponement of adjuvant therapy, number of outpatient visits as well as survival were analyzed. RESULTS: 81 patients were included, 19 patients received anti-PD-1 monotherapy followed by surgery and 62 patients underwent upfront surgery. Surgical duration was longer in the neoadjuvant group (p < 0.001), regardless of site and lymph nodes removed. Complications were observed in 63.2 % in neoadjuvant patients vs. 80.6 % in upfront patients (p = 0.13). The number of nurse outpatient visits was higher for neoadjuvant patients (p = 0.02) and increased with the number of removed lymph nodes (p = 0.05). The neoadjuvant patients started adjuvant therapy at median 6.0 weeks after surgery compared to 9.1 weeks in upfront (p < 0.001). At one year the overall survival was 100 % (95 % CI 100 - 100 %) in the neoadjuvant group and 90.3 % (95 % CI 83.3-98.0 %) in upfront surgery (P = 0.04). CONCLUSION: Neoadjuvant ICI did not increase postoperative complications. It was associated with prolonged surgical duration and increased follow-up visits, but also shorter time until starting adjuvant treatment.