CD274 and Merkel cell skin cancer: In advanced Merkel cell carcinoma, a rare immunogenic cutaneous cancer, nivolumab and ipilimumab combination therapy has demonstrated substantial benefit (objective response rate, 31%) even after prior anti-PD1/anti–PD-L1 exposure and a 100% objective response rate in the immune checkpoint inhibitor–naive setting, establishing the superiority of the combination in treating this cancer.15 Future randomized investigations in immunogenic cancers and biomarker-driven studies may identify combination-responsive cancers and subsets.