Targeted therapies of HER2-positive gastric adenocarcinoma

Worldwide, gastric cancer is the fifth common cancer type and causes the third most cancer-associated deaths (1), mostly due to its commonly fatal outcome especially in locally advanced or metastatic disease. For over a decade, standard of care in metastatic disease was based on chemotherapy doublets or triplets containing platinum agents plus fluoropyrimidine in combination with either taxanes or anthracyclines (2). Molecular subtyping of gastric adenocarcinoma has identified promising protooncogenes as novel therapeutic targets (3). One of them is the human epidermal growth factor receptor 2 (HER2/ERBB2), detected in a subset of roughly 9% to 18% of gastric adenocarcinomas (4).