PURPOSE: The aim of this study was to determine the risk factors for anastomotic leakage after laparoscopic rectal surgery.METHODS: We conducted a prospective trial involving 395 patients with stage 0/I rectal carcinoma who underwent laparoscopic low anterior resection using a double stapling technique. Data concerning variables related to patient background, tumors and surgical factors were evaluated. The outcomes with respect to anastomotic leakage were recorded, and univariate and multivariate analyses were performed to identify relevant risk factors.RESULTS: The overall anastomotic leakage rate was 8.4%. A univariate analysis showed male gender (P = 0.006) and preoperative blood sugar level (P = 0.0034) to be significantly associated with anastomotic leakage. The variables of gender, preoperative blood sugar level, American Society of Anesthesiologists (ASA) classification (P = 0.15), transanal decompression tube (P = 0.06) and number of stapler cartridges used for rectal transection (P = 0.18) were selected for the multivariate analysis because of their P values being <0.2. The multivariate analysis identified male gender (odds ratio 4.12, P = 0.006) and the absence of a transanal decompression tube (odds ratio 3.11, P = 0.0484) as independent risk factors predicting anastomotic leakage.CONCLUSIONS: Male gender and the absence of a transanal decompression tube appeared to be independent risk factors for anastomotic leakage. Insertion of a transanal decompression tube may help prevent anastomotic leakage after low anterior resection, particularly in male patients.