A phase II trial of endoscopic submucosal dissection for mucosal gastric cancer: Japan Clinical Oncology Group Study JCOG0607.

A Phase II trial was started in Japan to evaluate the efficacy and safety of endoscopic submucosal dissection for macroscopic mucosal (cT1a) gastric cancer beyond the present indication described in the Gastric Cancer Treatment Guidelines by the Japan Gastric Cancer Association. Patients with cT1a gastric cancer, which is histologically proven differentiated (intestinal) type adenocarcinoma, are eligible. In this study, the tumor is >2 cm for ulceration (UL)-negative cases or <or=3 cm for UL-positive cases. A total of 330 patients are enrolled from 26 institutions over 2 years. The primary endpoint is the 5-year overall survival (OS). The secondary endpoints are OS in the UL-negative subset and the UL-positive subset, recurrence-free survival (RFS), 5-year RFS with preserved stomach, proportion of en bloc resection, proportion of pathological curative resection and adverse events.