This randomized Phase II trial will compare the efficacy and safety of laparoscopy-assisted D2 distal gastrectomy and open distal D2 gastrectomy after neoadjuvant chemotherapy for patients with macroscopically resectable serosa-positive gastric cancer. When R0/R1 surgery is achieved, patients receive S-1 chemotherapy for 1-year post-operatively. The primary endpoint is the 3-year disease-free survival. The sample size to test the hypothesis of the non-inferiority of laparoscopy-assisted D2 distal gastrectomy to open distal D2 gastrectomy is 80. This trial will be able to appraise the use of the laparoscopic approach as a curative D2 distal gastrectomy after neoadjuvant chemotherapy for gastric cancer.