PDCD1 and melanoma: Subgroup analysis also revealed that the MAP2K1/2-mutated group was more likely to obtain clinical benefits from anti-CTLA-4 monotherapy, as compared to anti-PD-1 monotherapy (HR = 0.31; 95% CI, 0.11−0.85; Figure 3C), suggesting that for MAP2K1/2-mutated melanomas, the efficacy of anti-CTLA-4 therapy might be superior to that of anti-PD-1 therapy.