Impact of Anastomotic Leakage on Postoperative Survival of Patients with Colorectal Cancer: A Meta-analysis Using Propensity Score Matching Studies

Objective: To explore the influence of anastomotic leakage (AL) on postoperative survival in patients with colorectal cancer (CRC).

Background: Although several studies have compared the postoperative survival of patients with CRC with and without AL, the background characteristics of the two groups were not aligned in most studies.

Methods: We performed a comprehensive electronic search of the literature up to March 2020 to identify propensity score matching (PSM) studies that compared postoperative survival between CRC patients with and without AL. A meta-analysis was performed using random-effects models to calculate the risk ratio (RR) and 95% confidence interval (CI), and heterogeneity was analyzed using I (Akiyoshi et al., 2011) [2] statistics.

Results: Four PSM studies involving a total of 1676 patients with CRC undergoing surgery were included in this meta-analysis. Among 234 patients who had AL, 163 (69.7%) survived at 5 years after surgery, whereas among 1422 patients who did not have AL, 1156 (81.3%) survived at 5 years after surgery. Background characteristics of the two groups were adjusted with PSM in all 4 studies. The result of the meta-analysis revealed a significant difference between the two groups (RR, 1.63; 95% CI, 1.09-2.45; P = 0.02; I = 66%) in 5-year overall survival (OS).

Conclusions: The results of this meta-analysis demonstrate a significantly decreased 5-year OS in patients with CRC who had AL compared with patients with CRC who did not have AL.