The mOS was longer in the pembrolizumab group in all the Chinese patients (8.4 vs. 5.6 months; HR = 0.55, 95% CI: 0.36–0.82), in the ESCC (8.4 vs. 5.6 months; HR = 0.55, 95% CI: 0.37–0.83), and in the PD-L1 positive patients (12.0 vs. 5.3 months; HR = 0.34, 95% CI: 0.17–0.69). Here, CD274 is linked to esophageal squamous cell carcinoma.