Current Progress in Human Epidermal Growth Factor Receptor 2 Targeted Therapies in Esophagogastric Cancer.

Esophagogastric cancer is a worldwide health problem. The addition of the epidermal growth factor receptor 2 (HER2)-directed antibody trastuzumab to chemotherapy increased the overall survival of patients with metastatic HER2-positive esophagogastric cancer. This article discusses the available data to support HER2 as validated biomarker and recently completed and ongoing clinical trials of HER2-directed agents in metastatic and localized disease. Also reviewed is the mechanisms of resistance for HER2-directed therapy and ongoing research strategies including new imaging techniques and studies with patient-derived xenografts.