Prospective randomized trial of preoperative enteral immunonutrition followed by elective total gastrectomy for gastric cancer（OGSG0507）

Intraoperative versus extended antimicrobial prophylaxis after gastric cancer surgery: a phase 3, open-label, randomised controlled, non-inferiority trial（OGSG0501）

Phase II trial of preoperative S-1 plus cisplatin followed by surgery for initially unresectable locally advanced gastric cancer（EJSO2012）

Phase II feasibility study of adjuvant S-1 plus docetaxel for stage III gastric cancer patients after curative D2 gastrectomy（OGSG0403）

腹膜転移を伴う高度進行・再発胃癌におけるS-1+Paclitaxel併用療法のFeasibility試験（OGSG0401）

A Feasibility Study of UFT/LV and Irinotecan (TEGAFIRI) in Advanced or Metastatic Colorectal Cancer: Osaka Gastrointestinal Cancer Chemotherapy Study Group (OGSG) PROG 0304

Phase II Study of a Combination of S-1 and Paclitaxel in Patients with Unresectable or Metastatic Gastric Cancer（OGSG0105）

Multi-Center Phase II Study for Combination Therapy with Paclitaxel/Doxifluridine to Treat Advanced/Recurrent Gastric Cancer Showing Resistance to S-1 (OGSG0302)

Phase II study of a combination of iIrinotecan and S-1 in patients with advanced gastric cancer (OGSG0002)

Multicenter phase II study of irinotecan plus bolus fluoroutacil/l-leucovorin for metastasic colorectal cancer（OGSG0201）