CD274 and esophageal squamous cell carcinoma: In the 2022 Japanese guidelines for EC, nivolumab monotherapy is strongly recommended for ESCC with no prior anti-PD-L1 therapy and pembrolizumab monotherapy is weakly recommended for ESCC with a combined positive score of ≥ 10 and no prior anti-PD-L1 therapy or microsatellite instability-high or tumor mutational burden-high with no prior anti-PD-L1 antibody.