ERBB2 and gastric cancer: A cost-effectiveness analysis of the Tratuzumab for Gastric Cancer (ToGA) trial26, that compared trastuzumab with platinum-based chemotherapy versus chemotherapy alone for metastatic gastric cancer in patients with HER2 amplification or overexpression32, showed that patients with tumours demonstrating strong HER2 expression on immunohistochemistry (IHC) derived the most benefit, with an incremental QALY of 0.326 and an ICER of €55 000 compared with €83 000 in IHC2+/FISH+ or IHC3+ tumours and €110 000 in the HER2+ tumours.