PDCD1 and gastroesophageal junction adenocarcinoma: Importantly, anti-programmed cell death protein 1 (PD-1) has also been shown to improve survival in patients with stage II and III disease in the Checkmate-577 study, in which DFS was significantly higher in patients treated with adjuvant nivolumab compared to placebo in patients undergoing surgery after chemoradiotherapy for esophageal and GEJ adenocarcinoma, regardless of PD-L1 expression11.