ERBB2 and gastric cancer: The standard first-line chemotherapy for patients with erb-b2 receptor tyrosine kinase 2 (ERBB2, also known as HER2)-negative advanced GC (AGC) in Japan is a combination therapy with fluoropyrimidine plus platinum (e.g., S-1 or capecitabine plus cisplatin or oxaliplatin) [2–4].