ERBB2 and gastric cancer: In addition, recent research has shown that adding trastuzumab, a humanized monoclonal antibody targeting the human epidermal growth factor receptor 2 (HER2) protein, to chemotherapy (fluoropyrimidines and cisplatin) for patients with MUGC with HER2 overexpression and/or gene amplification (the so-called HER2-positive gastric cancer) has a significant superiority to chemotherapy alone in terms of overall survival (median survival 13.8 months with trastuzumab versus 11.1 months with chemotherapy alone) [4].