Development of a Risk Scoring System for Predicting Anastomotic Leakage Following Laparoscopic Rectal Cancer Surgery

Abstract

Purpose: To develop a risk scoring system that can predict the incidence of anastomotic leakage after laparoscopic rectal cancer surgery. Patients and Methods: The clinical data of 387 patients with rectal cancer who underwent laparoscopic low anterior resection were retrospectively collected. Univariable and multivariable logistic regression analyses were used to evaluate independent risk factors for postoperative anastomotic leakage. A simplified points system was then developed based on the corresponding regression coefficient β of each risk factor. Receiver operating characteristic (ROC) analysis was used to evaluate the performance and the optimal cut-off value in predicting anastomotic leakage. The performance of the points system was then externally validated in an independent cohort of 192 patients based in another institution. Results: Anastomotic leakage occurred in 36 of 387 patients with rectal cancer (9.30%). Logistic multivariable regression analysis showed that males, maximum tumor diameter (≥ 5cm), operation time (≥ 180min), preoperative chemoradiation, intraoperative blood transfusion and the anastomosis level from the anal verge (≤ 5cm) were independent risk factors for the incidence of anastomotic leakage. According to the scoring standard, the risk points of each patient were calculated. ROC analysis based on the risk points showed that the area under the curve (AUC) was 0.795 (95% CI:0.752– 0.834) and the optimal cut-off value was 6, yielding a sensitivity of 88.89% and a specificity of 62.96%. Using this risk points system, the AUC of another cohort of 192 patients from another institution who underwent laparoscopic low anterior resection for rectal cancer was 0.853 (95% CI:0.794– 0.900, p< 0.001) and patients with risk points ≥ 6 had a 21.05% chance of developing anastomotic leakage. Conclusion: This risk points system for predicting anastomotic leakage following laparoscopic rectal cancer surgery may be useful for surgeons in their decisions to perform intraoperative diversion stoma, which can reduce the incidence of postoperative anastomotic leakage.