Ongoing clinical studies of minimally invasive surgery for gastric cancer in Japan.

Since the development of laparoscopy-assisted distal gastrectomy (LADG) with lymph node dissection for gastric cancer in Japan, this type of surgery is improving and evolving. To establish high-quality evidence of laparoscopic gastrectomy (LAG) in the field of gastric cancer treatments, two large-scale, prospective randomized controlled trials have been performed in Japan; the Japan Clinical Oncology Study Group (JCOG) 0912 for early disease and the Japanese Laparoscopic Surgery Study Group (JLSSG) 0901 for advanced disease. Analyses using mega-data from the National Clinical Database (NCD) have also been carried out as a clinical study to clarify the safety of LAG. Furthermore, as advanced laparoscopic techniques have been developed, prospective clinical studies are being performed with regard to laparoscopy-assisted total gastrectomy (LATG), robotic gastrectomy, and minimally invasive surgery with sentinel node (SN) navigation. This review summarizes the current status of minimally invasive surgeries for gastric cancer based on the latest ongoing clinical trials in Japan.