Single-arm confirmatory trial of laparoscopy-assisted total or proximal gastrectomy with nodal dissection for clinical stage I gastric cancer: Japan Clinical Oncology Group study JCOG1401

Laparoscopy-assisted distal gastrectomy (LADG) for gastric cancer is safe and feasible. In contrast, no prospective study evaluating the safety and efficacy of laparoscopy-assisted total gastrectomy (LATG) or laparoscopy-assisted proximal gastrectomy (LAPG) has been completed. We conducted a single-arm confirmatory trial to evaluate the safety of LATG/LAPG for clinical stage I (T1N0/T1N1/T2N0) proximal gastric cancer. The extent of lymphadenectomy was selected based on the Japanese Gastric Cancer Treatment Guidelines. The mini-laparotomy incision was required to be ≤ 6 cm. The primary endpoint was the proportion of grade 2–4 (CTCAE ver. 4.0) esophagojejunal anastomotic leakage. The planned sample size was 245 considering a threshold of 8% and one-sided alpha of 2.5%. Between April 2015 and February 2017, 244 eligible patients were enrolled. LATG/LAPG was performed in 195/49. The proportion of conversions was 1.7%. Clinical T1N0/T1N1/T2N0 was 212/9/23. The extents of lymphadenectomy were as follows: D1+: 229; D2: 15. The median operation time was 309 min (IQR 265–353). The median blood loss was 30 ml (IQR 10–86). Grade 2–4 esophagojejunal anastomotic leakage was 2.5% (6/244; 95% CI 0.9–5.3). The overall proportion of in-hospital grade 3–4 adverse events was 29% (71/244). The proportions of intraabdominal abscess and pancreatic fistula were 3.7% and 2.0%, respectively. There were no treatment-related deaths. This trial confirmed the safety of LATG/LAPG. After the non-inferiority of LADG is confirmed in our phase III trial (JCOG0912), LATG/LAPG is expected to be established as one of the standard treatments for clinical stage I gastric cancer.