In 2021, the immune checkpoint inhibitors nivolumab and pembrolizumab were approved in Europe for 1L treatment of adults with HER2-negative advanced or metastatic gastric, GEJ, or esophageal adenocarcinoma whose tumors express PD-L1 with a CPS ≥ 5 for nivolumab and ≥10 for pembrolizumab [21,22]. This evidence concerns the gene CD274 and esophageal adenocarcinoma.