Gastrectomy With Or Without Omentectomy For Ct3-4 Gastric Cancer: A Multicentre Cohort Study

Background Omentectomy is performed widely for locally advanced gastric cancer to prevent disease recurrence. However, its clinical benefit is unknown.Methods This retrospective cohort study compared the outcome of gastrectomy with preservation of the omentum (GPO) and gastrectomy with resection of the omentum (GRO) among patients with cT3-T4 gastric cancer who underwent gastrectomy between 2006 and 2012 in one of five participating institutions. A consensus conference identified 28 variables potentially associated with outcome after gastrectomy for the estimation of propensity scores, and propensity score matching (PSM) was undertaken to control for possible confounders. Postoperative surgical outcomes, overall survival and disease recurrence were compared between GPO and GRO.Results A total of 1758 patients were identified, of whom 526 remained after PSM, 263 in each group. Median follow-up was 4 center dot 9 (i.q.r. 3 center dot 1-5 center dot 9) years in the GRO group and 5 center dot 0 (2 center dot 5-6 center dot 8) years in the GPO group. The incidence of postoperative complications of Clavien-Dindo grade III or more was significantly higher in the GRO group (17 center dot 5 versus 10 center dot 3 per cent; P = 0 center dot 016). Five-year overall survival rates were 77 center dot 1 per cent in the GRO group and 79 center dot 4 per cent in the GPO group (P = 0 center dot 749). There were no significant differences in recurrence rate or pattern of recurrence between the groups.Conclusion Overall survival and disease recurrence were comparable in patients with cT3-4 gastric cancer who underwent GPO or GRO.