The inhibition of HER2 with the monoclonal antibody trastuzumab in patients with HER2-amplified/overexpressed advanced-stage gastric or esophagogastric-junction adenocarcinomas, confers an improved response rate, progression-free survival, and overall survival when trastuzumab is combined with cisplatin and fluoropyrimidine [5]. Here, ERBB2 is linked to gastroesophageal junction adenocarcinoma.