Comparison of symptomatic anastomotic leakage following laparoscopic and open low anterior resection for rectal cancer: a propensity score matching analysis of 1014 consecutive patients

Background: This observational study was conducted to compare the rate of symptomatic anastomotic leakage (AL), as defined by precise criteria, between laparoscopic and open surgery in patients with mid-to-low rectal cancer using a relatively novel statistical technique. Methods: A total of 1014 consecutive low anterior resection (LAR) patients were registered, of whom 936 were included in this prospective, multicenter, and cohort study (UMIN-CTR, Number 000004017). Patients with rectal cancer within 10 cm from the anal verge underwent either open or laparoscopic LAR at one of the 40 institutions in Japan from June 2010 to February 2013. The primary endpoint of this study was to compare the rate of symptomatic AL between the two groups before and after propensity score matching (PSM). The secondary endpoint was to analyze the risk factors for symptomatic AL in open and laparoscopic surgery. Results: After PSM, the incidence of symptomatic AL in open and laparoscopic surgery was 12.4 and 15.3 %, respectively (p = 0.48). AL requiring relaparotomy occurred after 3.8 % of open surgeries and 6.2 % of laparoscopic surgeries (p = 0.37). Multivariate analysis identified male gender as an independent risk factor for symptomatic AL following laparoscopic surgery (p = 0.001; odds ratio 5.2; 95 % CI 2.0–13.8), and male gender (p = 0.004; odds ratio 2.6; 95 % CI 1.3–5.6), tumor size (p = 0.002; odds ratio 1.2; 95 % CI 0.7–0.9), and number of stapler firing (p = 0.04; odds ratio 4.1; 95 % CI 1.0–15.0) following open surgery. Conclusion: The rate of symptomatic AL was comparable following laparoscopic and open LAR in this large, multicenter, cohort study after PSM. Male gender was associated with an increased risk of symptomatic AL after laparoscopic LAR.