ERBB2 and esophageal adenocarcinoma: Landmark clinical trials reported within the past decade which have informed current clinical practice, have demonstrated only modest improvements (6–9%) in OS with peri‐operative chemotherapy for esophageal adenocarcinoma or a 26% improvement in overall survival with trastuzumab therapy for HER‐2‐positive advanced esophageal adenocarcinoma 53, 54.