ERBB2 and breast cancer: Trastuzumab (Herceptin; Genentech, South San Francisco, CA), developed as a humanized monoclonal antibody and directed against the extracellular domain of the HER-2 receptor, has been confirmed to significantly improve overall survival and progression-free survival in patients with HER2-overexpressed breast cancer, including early, locally advanced and metastatic breast cancer [9, 10].