CD274 and esophageal squamous cell carcinoma: Of the 74 patients assigned to the pembrolizumab–chemotherapy group, 67 (90.5%) had ESCC, 48 (64.9%) had PD-L1 CPS ≥ 10, and 44 (59.5%) had ESCC PD-L1 CPS ≥ 10.