CD274 and esophageal squamous cell carcinoma: CheckMate 648 showed that overall survival (OS) and progression-free survival (PFS) were significantly longer with nivolumab plus chemotherapy or ipilimumab than chemotherapy alone in all randomly assigned patients with ESCC, without reporting the Kaplan‒Meier (KM) curves for patients with absent or low PD-L1 expression (Doki et al., 2022).