Fluoropyrimidine plus platinum-based chemotherapy remains the standard first-line therapy for patients with non-operative radical or human epidermal growth factor 2 (HER2)-negative advanced or metastatic GC/GEJC by the National Comprehensive Cancer Network (NCCN), the European Society for Medical Oncology (ESMO), and the Chinese Society of Clinical Oncology (CSCO) (5–7), despite poor efficacy. This evidence concerns the gene ERBB2 and gastric cancer.