Meta-analysis of the risk factors for ananstomotic leakage after anterior resection of rectal cancer in China

Objective To investigate the risk factors of anastomotic leakage after anterior resection for cancer of rectum. Methods A Meta analysis was conducted among all the studies published in China from Jun 2002 to Jun 2012. Results Nineteen studies met the inclusion criteria with a total of 6454 patients. The overall positive rate of anastomotic leakage was 6.79%. The risk of anastomotic leakage was significantly increased in male compared with female (OR=1.79, 95% CI = 1.44-2.23, P < 0.001). Those patients who had preoperative complications such as diabetes mellitus, anemia, hypoalbuminemia and intestinal obstruction were associated with higher risk for anastomotic leakage. The OR was 2.41 (95% CI = 1.78-3.26, P < 0.001), 1.74 (95% CI = 1.12-2.71, P = 0.01), 3.18 (95% CI = 1.63-6.18, P < 0.001), 4.47 (95% CI = 2.69-7.45, P < 0.001), respectively. With regard to the Duke's stage, stage C and D had a higher risk of anastomotic leakage than stage A and B (OR = 1.63, 95% CI = 1.22-2.17, P < 0.001). The distance between lower margin of tumor and anal verge was also a risk factor of anastomotic leakage among patients with ≥7 cm vs < 7 cm (OR = 3.09, 95% CI = 1.07-8.98, P = 0.04). However, age, the approach of anastomosis and the size and degree of malignancy of tumor were not correlated to anastomotic leakage. Conclusions The common risk factors of anastomotic leakage after anterior resection of rectal carcinoma in China are gender, preoperative complications such as diabetes, anemia, hypoalbuminemia and intestinal obstruction, Duke's stage, the distance between the lower margin of tumor and anal verge. Key words: Rectal cancer; Anastomotic leakage; Risk factors; Meta analysis