Influencing Factors of Symptomatic Anastomotic Leakage After Anterior Resection of the Rectum for Cancer

The aim of the present study was to analyze the factors associated with anastomotic leakage after anterior resection for rectal cancer. Retrospectively collected consecutive data of 738 rectal cancer patients who underwent anterior resection in our hospital between 2005 and 2008 were reviewed. The associations between 15 patient-related and surgery-related variables and anastomotic leakage were studied with both the univariate chi-square test and multivariate logistic regression analysis. Univariate analysis showed that risk factors associated with anastomotic leakage were low rectal cancer (located 5 cm or less above the dentate line) (5.9% vs. 0.9%; P = 0.003), non-specialized surgeon (3.9% vs. 11.3%; P = 0.031), and defunctioning transanal catheter placement (14.5% vs. 3.6%; P < 0.001). It should be noted that the mean surgeon case volumes of anterior resection of colorectal surgeons and non-specialized general surgeons were 43 per year and 2 per year, respectively (P < 0.001). In addition, there was a tendency for colorectal surgeons to operate on a greater proportion of low rectal cancers (72.1% vs. 52.8%; P = 0.003). In the multivariate analysis, besides low rectal cancer, non-specialized surgeon, and transanal catheter placement, three other factors were associated with anastomotic leakage: diabetes mellitus (P = 0.027), free distal margins less than 1 cm (P = 0.009), and a defunctioning stoma (P = 0.031). In a further analysis of 522 patients with low rectal cancer, the leakage rate in patients with a defunctioning stoma was significantly lower (2.9% vs. 8.5%; P = 0.007). By contrast, the leakage rate in the transanal catheter placement group was higher (15.1% vs. 4.9%; P = 0.008), because of its poor protective effect as well as the selection bias. From the findings of this study, we believe that low rectal cancer, non-specialized surgeons, and diabetes mellitus are risk factors for anastomotic leakage after rectal surgery, and that a defunctioning stoma could significantly reduce the incidence of leakage in low rectal cancer patients.