CD274 and esophageal squamous cell carcinoma: Compared with PD-L1 CPS < 10 patients, advanced ESCC patients with PD-L1 CPS ≥ 10 achieved better median PFS (7.1 months vs. 5.7 months) and OS (18.6 months vs. 14.2 months) outcomes from serplulimab in combination with chemotherapy.