In this study, although our six patients with EBV ( +) gastric cancer (5 in the nivolumab and 1 in the placebo group) also showed a trend toward a high percentage (4/6, 66.7%) of tumor PD-L1 CPS (≥ 1%) compared with those of patients with EBV ( −) gastric cancer (9/30, 30%), 2 out of 5 EBV ( +) patients in the nivolumab group showed early progressive disease (Figure S2). This evidence concerns the gene CD274 and gastric cancer.