Combined Surgery and Extensive Intraoperative Peritoneal Lavage vs Surgery Alone for Treatment of Locally Advanced Gastric Cancer The SEIPLUS Randomized Clinical Trial

IMPORTANCE Peritoneal metastasis is the most frequent pattern of postoperative recurrence in patients with gastric cancer. Extensive intraoperative peritoneal lavage (EIPL) is a new prophylactic strategy for treatment of peritoneal metastasis of locally advanced gastric cancer; however, the safety and efficacy of EIPL is currently unknown. OBJECTIVE To evaluate short-term outcomes of patients with advanced gastric cancer who received combined surgery and EIPL or surgery alone. DESIGN, SETTING, AND PARTICIPANTS From March 2016 to November 2017, 662 patients with advanced gastric cancer receiving D2 gastrectomy were enrolled in a large, multicenter, randomized clinical trial from 11 centers across China. In total, 329 patients were randomly assigned to receive surgery alone, and 333 patients were randomly assigned to receive surgery plus EIPL. Clinical characteristics, operative findings, and postoperative short-term outcomes were compared between the 2 groups in the intent-to-treat population. MAIN OUTCOMES AND MEASURES Short-term postoperative complications and mortality. RESULTS The present analysis included data from 550 patients, 390 men and 160 women, with a mean (SD) age of 60.8 (10.7) years in the surgery alone group and 60.6 (10.8) in the surgery plus EIPL group. Patients assigned to the surgery plus EIPL group exhibited reduced mortality (0 of 279 patients) compared with those assigned to surgery alone (5 of 271 patients [1.9%]) (difference, 1.9%; 95% CI, 0.3%-3.4%; P=.02). A significant difference in the overall postoperative complication rate was observed between patients receiving surgery alone (46 patients [17.0%]) and those receiving surgery plus EIPL (31 patients [11.1%]) (difference, 5.9%; 95% CI, 0.1%-11.6%; P=.04). Postoperative pain occurred more often following surgery alone (48 patients [17.7%]) than following surgery plus EIPL (30 patients [10.8%]) (difference, 7.0%; 95% CI, 0.8%-13.1%; P=.02). CONCLUSIONS AND RELEVANCE Inclusion of EIPL can increase the safety of D2 gastrectomy and decrease postoperative short-term complications and wound pain. As a new, safe, and simple procedure, EIPL therapy is easily performed anywhere and does not require any special devices or techniques. Our study suggests that patients with advanced gastric cancer appear to be candidates for the EIPL approach.