PDCD1 and Skin rash: Compared with chemotherapy in Group B, it was found that PD-1 or PD-L1 together with chemotherapy significantly increased the risk of rash for all grades (OR = 1.87, 95% CI: [1.59, 2.20]; I2 = 53%, Z = 7.50, p < 0.00001; Figures 3(a)–3(d)), even in each evaluable subgroups (Figures 3(c) and 3(d)).