ERBB2 and gastric cancer: The phase III “Trastuzumab for Gastric Cancer” ToGA trial demonstrated a statistically significant improvement of median OS from 11.1 to 13.8 months by the addition of the HER2-targeting antibody trastuzumab to a platinum and fluorouracil (5-FU) based doublet chemotherapy in HER2 positive gastric/GEJ cancer [7], and since then has become the standard first-line regimen in HER2 positive disease [9,10].