Outcomes of adjuvant pembrolizumab in stage II melanoma: post hoc analysis by primary tumor location

In the multinational phase 3 KEYNOTE-716 trial, recurrence-free survival (RFS) and distant metastasis-free survival (DMFS) were significantly improved with adjuvant pembrolizumab over placebo after resection of stage IIB or IIC melanoma. Post-hoc analysis of the trial evaluated the efficacy of adjuvant pembrolizumab versus placebo in subgroups according to primary tumor location (head-neck, trunk, or extremities). The HRs (pembrolizumab versus placebo) for RFS were 0.60 (95% CI 0.38-0.93) for the head-neck subgroup, 0.57 (0.38-0.84) for the trunk subgroup, and 0.69 (0.47-1.02) for the extremities subgroup, whereas the HRs for DMFS were 0.65 (0.37-1.14) for the head-neck subgroup, 0.59 (0.38-0.92) for the trunk subgroup, and 0.53 (0.31-0.90) for the extremities subgroup. The authors conclude that RFS and DMFS consistently favored adjuvant pembrolizumab over placebo in most subgroups analyzed in this post hoc analysis from the KEYNOTE-716 trial.