The forest plots show that the pooled ORR was significantly higher for NPC patients with PD-L1 ≥ 1% (ORR = 0.37, 95% CI: 0.29–0.46) than for those with PD-L1 < 1% (ORR = 0.22, 95% CI: 0.17–0.28) (subgroup difference, P < 0.01) (Figure 3A). This evidence concerns the gene CD274 and nasopharyngeal carcinoma.