Then, we explored the subgroup of OS in patients treated with combination PD-1/PD-L1 inhibitors, and found that the PD-1/PD-L1 inhibitor group only showed OS benefit in patients with NSCLC, SCLC, ESCC and melanoma (Figure 2; Supplementary Figure S10). Here, PDCD1 is linked to esophageal squamous cell carcinoma.