| Gastric cancer is very common cancer in Asia especially in Korea, Japan and China . Through collaboration among doctors in these countries, we can answer clinical questions quickly. Examples of these international collaborations would be CLASSIC, REGATTA, Neoadjuvant imatinib in large gastric GIST, EXPEL, CONVO-GC and so on. Whether the addition of gastrectomy to chemotherapy improves survival for patients with advanced gastric cancer with a single non-curable factor remains controversial. Japanese and Korean doctors investigate the superiority of gastrectomy followed by chemotherapy versus chemotherapy alone with respect to overall survival in these patients. It was an open-label, randomised, phase 3 trial at 44 centres or hospitals in Japan, South Korea, and Singapore. Patients aged 20-75 years with advanced gastric cancer with a single non-curable factor confined to either the liver (H1), peritoneum (P1), or para-aortic lymph nodes (16a1/b2) were randomly assigned (1:1) in each country to chemotherapy alone or gastrectomy followed by chemotherapy. Chemotherapy consisted of oral S-1 80 mg/m(2) per day on days 1-21 and cisplatin 60 mg/m(2) on day 8 of every 5-week cycle. Gastrectomy was restricted to D1 lymphadenectomy without any resection of metastatic lesions. The primary endpoint was overall survival, analysed by intention to treat. Total 175 patients were randomly assigned to chemotherapy alone (86 patients) or gastrectomy followed by chemotherapy (89 patients). After the first interim analysis on Sept 14, 2013, the predictive probability of overall survival being significantly higher in the gastrectomy plus chemotherapy group than in the chemotherapy alone group at the final analysis was only 13.2%, so the study was closed on the basis of futility. Overall survival at 2 years for all randomly assigned patients was 31.7% (95% CI 21.7-42.2) for patients assigned to chemotherapy alone compared with 25.1% (16.2-34.9) for those assigned to gastrectomy plus chemotherapy. Median overall survival was 16.6 months (95% CI 13.7-19.8) for patients assigned to chemotherapy alone and 14.3 months (11.8-16.3) for those assigned to gastrectomy plus chemotherapy (hazard ratio 1.09, 95% CI 0.78-1.52; one-sided p=0.70). The incidence of the following grade 3 or 4 chemotherapy-associated adverse events was higher in patients assigned to gastrectomy plus chemotherapy than in those assigned to chemotherapy alone. One treatment-related death occurred in a patient assigned to chemotherapy alone (sudden cardiopulmonary arrest of unknown cause during the second cycle of chemotherapy) and one occurred in a patient assigned to chemotherapy plus gastrectomy (rapid growth of peritoneal metastasis after discharge 12 days after surgery). Since gastrectomy followed by chemotherapy did not show any survival benefit compared with chemotherapy alone in advanced gastric cancer with a single non-curable factor, gastrectomy cannot be justified for treatment of patients with these tumors.