The anti-HER2 antibody trastuzumab, in combination with chemotherapy, has improved clinical outcomes in HER2+ advanced gastric cancer,2 and trastuzumab is the recommended first-line therapy in combination with oxaliplatin or cisplatin, and 5-fluorouracil or capecitabine for patients with HER2+ metastatic gastric cancer.3 Here, ERBB2 is linked to gastric cancer.