Therapy with humanized HER2 mAb targeting different members of the epidermal growth factor receptor (EGFR) family combined with cytostatic agents e.g., docetaxel and potentially tyrosine kinase inhibitors such as, e.g., lapatinib or neratanib/afatinib has clearly improved the outcome of patients with metastatic breast or gastric cancer (6, 10–12). This evidence concerns the gene ERBB2 and gastric cancer.