Adjuvant Pembrolizumab in Stage II Melanoma: Outcomes by Primary Tumor Location in the Randomized, Double-Blind, Phase III KEYNOTE-716 Trial.

Previous results from the KEYNOTE-716 trial demonstrated significantly improved recurrence-free survival (RFS) and distant metastasis-free survival (DMFS) with adjuvant pembrolizumab versus placebo in patients with resected stage IIB or IIC melanoma. We present a post hoc analysis of efficacy according to primary tumor location. KEYNOTE-716 (NCT03553836) is a randomized, multicenter, double-blind, phase III study. Patients aged ≥ 12 years with newly diagnosed, resected stage IIB or IIC melanoma (sentinel node-negative) were randomly assigned (1:1) to pembrolizumab 200 mg every 3 weeks (2 mg/kg up to 200 mg for pediatric patients) or placebo. This post hoc analysis evaluated RFS and DMFS by primary tumor location of the head/neck, trunk, or extremities. Overall, 976 patients were assigned to pembrolizumab (n = 487) or placebo (n = 489). Median follow-up was 39.4 months (range 26.0–51.4). The hazard ratios HRs (95