CD274 and esophageal squamous cell carcinoma: The benefit of pembrolizumab–chemotherapy was also consistent in patients with esophageal squamous cell carcinoma (ESCC), programmed cell death ligand 1 (PD-L1) combined positive score (CPS) ≥ 10, and ESCC PD-L1 CPS ≥ 10 [6].