[Influence of visceral lipids obesity on the early postoperative complications after radical gastrectomy]

Objective: To investigate the effect of visceral fat area (VFA) on the surgical efficacy and early postoperative complications of radical gastrectomy for gastric cancer. Methods: A retrospective cohort study method was used. Clinicopathological data and preoperative imaging data of 195 patients who underwent D2 radical gastric cancer surgery at the First Affiliated Hospital of Xi'an Jiaotong University from January 2014 to December 2017 were analyzed retrospectively. Inclusion criteria: (1) complete clinicopathological and imaging data; (2) malignant gastric tumor diagnosed by preoperative pathology, and gastric cancer confirmed by postoperative pathology; (3) no preoperative complications such as bleeding, obstruction or perforation, and no distant metastasis. Those who had a history of abdominal surgery, concurrent malignant tumors, poor basic conditions, emergency surgery, palliative resection, and preoperative neoadjuvant therapy were excluded. The VFA was calculated by software and VFA ≥ 100 cm² was defined as visceral obesity according to the Japan Obesity Association criteria . The patients were divided into high VFA (VFA-H, VFA≥100 cm², n=96) group and low VFA (VFA-L, VFA<100 cm², n=99) group . The clinicopathological characteristics, surgical outcomes and early postoperative complications were compared between the two groups. Univariate and multivariate Logistic regression models were used to analyze the risk factors of early complications. Receiver operating characteristic (ROC) curve was used to analyze predictive values of VFA for early complications. Pearson's χ² test was used to analyze the correlation between BMI and VFA. Results: There were no significant differences in terms of gender, age, American Society of Anesthesiologists physical status classification, preoperative comorbidities, preoperative anemia, tumor TNM staging, N staging, T staging and tumor differentiation, surgical method, extent of resection, and tumor location between the VFA-L group and the VFA-H group (all P>0.05). However, patients in the VFA-H group had higher BMI, larger tumor, lower rate of hypoalbuminemia and greater subcutaneous fat area (SFA) (all P<0.05). The VFA-H group presented significantly longer operation time and significantly less number of harvested lymph nodes as compared to the VFA-L group (both P<0.05). However, there were no significant differences in intraoperative blood loss, conversion to laparotomy and postoperative hospital stay (all P>0.05). Complications of Clavien-Dindo grade II and above within 30 days after operation were mainly anastomosis-related complications (leakage, bleeding, infection and stricture), intestinal obstruction and incision infection. The VFA-H group had a higher morbidity of early complications compared to the VFA-L group [24.0% (23/96) vs 10.1% (10/99), χ²=6.657, P=0.010], and the rates of anastomotic complications and incision infection were also higher in the VFA group [10.4% (10/96) vs. 3.0% (3/99), χ²=4.274, P=0.039; 7.3% (7/96) vs. 1.0% (1/99), P=0.033]. Multivariate logistic analysis showed that high BMI (OR=3.688, 95%CI: 1.685-8.072, P=0.001) and high VFA (OR=2.526, 95%CI: 1.148-5.559,P=0.021) were independent risk factors for early complications. The area under the ROC curve (AUC) of VFA for predicting early complications was 0.645, which was higher than that of body weight (0.591), BMI (0.624) and SFA (0.626). Correlation analysis indicated that there was a significantly positive correlation between BMI and VFA (r=0.640, P<0.001). Conclusion: VFA ≥ 100 cm² is an independent risk factor for early complications after radical gastrectomy for gastric cancer.It can better predict the occurrence of above early postoperative complications.