ERBB2 and gastroesophageal junction adenocarcinoma: In contrast to the failure to improve outcome by the majority of targeted agents in gastric cancers, a phase III trial demonstrated that trastuzumab, a HER-2 monoclonal antibody, substantially enhanced the response rate and overall survival of a group of patients with HER-2 overexpressing gastric cancer, including patients with GEJ adenocarcinoma [50], [57].