MAb-based treatment of cancer has been established as a therapeutic strategy for several hematologic and solid tumours, including those that target tumour antigens, anti-human epidermal growth factor receptor 2 (HER2) (e.g. trastuzumab), anti-CD20 (e.g. rituximab) and anti-epidermal growth factor receptor (EGFR) (e.g. cetuximab). This evidence concerns the gene ERBB2 and cancer.