Based on the results of a previous randomized controlled trial, the sixth edition of the Japanese Gastric Cancer Treatment Guidelines defines a regimen combining a platinum-based agent and a fluorouracil-based agent, including S-1 plus oxaliplatin (SOX), capecitabine plus oxaliplatin (CapeOX), and FOLFOX, as an acceptable first-line chemotherapy regimen for patients with epidermal growth factor receptor 2 (HER2)-negative AGC [2]. The gene discussed is ERBB2; the disease is gastric cancer.