Adverse events associated with postoperative outcomes of adjuvant anti-PD-1 antibody therapy in both acral and non-acral cutaneous melanomas: A multicenter, observational, post hoc analysis study.

Since anti-PD-1 Abs can cause irreversible immune-related adverse events (irAEs), the associations between their efficacies and the incidence of irAEs are important to evaluate the use of anti-PD-1Abs for the treatment of melanoma, especially in the adjuvant setting. The purpose of this post hoc analysis study was to retrospectively analyze the associations between recurrence-free survival (RFS) at 12 months and the onset of any irAEs in 31 non-acral cutaneous and 30 acral melanoma cases treated with anti-PD-1 Abs therapy at the adjuvant setting in Asians. There were 20 cases with greater than grade 1 AEs in both the acral and non-acral cutaneous groups. Of the acral melanoma, 10 cases were nails or toes, and 20 cases were soles and heels. The log-rank test showed that RFS was better in cases with AEs than in cases without AEs. The present study suggested that the different profiles of irAEs between non-acral cutaneous and acral melanoma might correlate with the different response to anti-PD1 Abs of melanoma in the adjuvant setting.