Preoperative treatment for marginally resectable metastatic melanoma: A single center experience in China.

Abstract

e22096 Background: Large randomized trials have proved that targeted therapy (TT) and immunotherapy (IT) can improve RFS for resectable Stage III melanoma. However, there is still a risk around 15%~25% of relapse within 1 year, especially worse for Stage IIID disease. Several neoadjuvant trials have shown a potentiality of long-term relapse-free after a pathologic complete response, especially for immunotherapy. We conducted a prospective study to investigate the impact of preoperative treatment on the anti-tumor efficacy and disease-free survival for Chinese melanoma. Methods: Stage IIID patients with matted nodes were recruited. For BRAF V600E-muted patients, Vemurafenib (V) was given for one months ahead of the surgery. For BRAF-wide-type patients, anti-PD1 antibody, Pembrolizumab(P) or Toripalimab (T) was given one dose per 3 weeks until response or intention-to-progression was observed. Pathologic assessment followed the principles for neoadjuvant therapy established by INMC. Results: Totally seven patients have been recruited. Detail information was listed in Table. Clinical ORR was 71%, however with no pCR observed. One patient in Vemurafenib group occurred brain mets within 1 month after surgery. All four patients in anti-PD1 group were relapse-free so far after median follow-up of 11 months. Conclusions: Preoperative BRAF targeted and anti-PD1 immunotherapy might guarantee a positive impact on anti-tumor response and local disease control for marginally resectable melanoma. However, the pathological criteria for neoadjuvant treatment might not be suitable to evaluate the matted or bulky specimen after preoperative treatment. [Table: see text]