An interim analysis of the KEYNOTE-811, a randomized, global phase III study evaluating trastuzumab plus platinum and fluoropyrimidine doublet chemotherapy +/- pembrolizumab for unresectable or metastatic HER2-positive esophagogastric adenocarcinomas revealed that addition of the checkpoint inhibitor significantly induces tumor shrinkage and improves objective response rate [52]. The gene discussed is ERBB2; the disease is gastroesophageal junction adenocarcinoma.