Objective To investigate the influencing factors for gastrointestinal leakage and its occurrence time after minimally invasive radical gastrectomy for gastric cancer.

Methods The retrospective case‑control study was conducted. The clinicopathological data of 3 135 patients with gastric cancer who were admitted to The First Affiliated Hospital of Army Medical University from January 2004 to December 2022 were collected. There were 2 174 males and 961 females, aged (57±11)years. Gastrointestinal leakage occurring within 4 days after surgery was defined as early gastrointestinal leakage, and gastrointestinal leakage occuring more than 4 days after surgery was defined as late gastrointestinal leakage. Measurement data with normal distribution were represented as Mean±SD, and t test was used for comparison between groups. Measurement data with skewed distribution were represented as M(Q₁,Q₃), and Mann‑Whitney U test was used for comparison between groups. Count data were represented as absolute numbers, and chi‑square test or Fisher exact pro-bability was used for comparison between groups. Comparison of ordinal data was conducted using the nonparameter rank sum test. Logistic regression model was used for univariate analysis, and Logistic forward stepwise regression model was used for multivariate analysis.

Results (1) Clinico-pathological characteristics of patients with and without postoperative gastrointestinal leakage. Of the 3 135 patients, there were 3 056 patients without gastrointestinal leakage and 79 patients with gastrointestinal leakage after operation, and there were significant differences in age, American Society of Anesthesiologists classification, neoadjuvant chemotherapy, surgical resection range, volume of intraoperative blood loss and surgeon′s experience between them (P<0.05). (2) Postoperative gastro-intestinal leakage and treatment. Of the 79 patients with postoperative gastrointestinal leakage, there were 36 patients with esophagojejunal anastomotic leakage (2 patients combined with jejunal anastomotic leakage), 29 patients with duodenal stump leakage, 11 patients with gastrojejunal anas-tomotic leakage, 2 patients with esophagogastric anastomotic leakage and 1 patient with gastroduo-denal anastomotic leakage. The same patient could be combined with more than one kind of gastro-intestinal leakage. Thirty‑four patients were improved after conservative treatment, 31 patients were improved after puncture drainage or endoscopic interventional therapy, and 14 patients were treated with secondary surgery. Among the patients who underwent secondary surgery, 5 patients died during perioperative period. The time to occurrence of postoperative gastrointestinal leakage of 79 patients was 5(4, 8)days, with the earliest occurrence at 1 day after operation, and the latest occurrence at 16 days after operation. (3) Analysis of influencing factors for the occurrence time of postopera-tive gastrointestinal leakage. Results of multivariate analysis showed that neoadjuvant chemotherapy, total gastrectomy and surgeon′s experience ≤50 patients were independent risk factors for early gastrointestinal leakage after minimally invasive radical gastrectomy for gastric cancer (odds ratio=4.262, 2.179, 5.015, 95% confidence interval as 1.386-13.110, 1.026-4.627, 2.378-10.537, P<0.05). Age>60 years, total gastrectomy, volume of intraoperative bleeding loss>200 mL were independent risk factors for late gastrointestinal leakage after minimally invasive radical gastrectomy for gastric cancer (odds ratio=3.031, 2.804, 2.223, 95% confidence interval as 1.631-5.631, 1.535-5.122, 1.190-4.151, P<0.05).

Conclusions Most patients with gastrointestinal leakage after minimally invasive radical gastrectomy for gastric cancer can be cured by non‑surgical methods. Neoadjuvant chemo-therapy and surgeon′s experience ≤ 50 patients are independent risk factors for early gastrointes-tinal leakage after minimally invasive radical gastrectomy. Age >60 years and volume of intraopera-tive blood loss >200 mL are independent risk factors for late gastrointestinal leakage after minimally invasive radical gastrectomy. Total gastrectomy is an independent risk factor for both early and late gastrointestinal leakage after minimally invasive radical gastrectomy for gastric cancer.