Randomized controlled Phase III trial to evaluate omentum preserving gastrectomy for patients with advanced gastric cancer (JCOG1711, ROAD-GC).

Gastrectomy with omentectomy and D2 lymph node dissection is the current standard procedure for locally advanced gastric cancer. However, some retrospective studies have reported that omentectomy increased post-operative abdominal complications but provided no survival advantage over omentum preservation. Therefore, we plan a randomized controlled phase III trial to confirm the non-inferiority of omentum preservation compared with omentectomy in patients with cT3 (SS) or cT4a (SE) gastric cancer. A total of 1050 patients will be enrolled from 62 institutions over a period of 6.5 years. The primary end point is relapse-free survival, and the secondary end points are overall survival, blood loss, operation time and adverse events. This trial has been registered at the UMIN Clinical Trials Registry as UMIN000036253.