Does neoadjuvant therapy increase the incidence of anastomotic leakage after anterior resection for mid and low rectal cancer? A systematic review and meta-analysis.

Aim To evaluate the association of neoadjuvant therapy with increases in the incidence of anastomotic leakage (AL) after middle and low rectal anterior resection. Method Electronic databases of Pubmed, Web of science, Scoupus and OVID were searched between 1980 and 2015. The random effect model was used to model the pooled data to determine the odds ratio (OR) with a 95% confidence interval (CI). Heterogeneity was evaluated using the Q test and I2 statistics. Subgroup, sensitivity and meta-regression analysis was conducted to explore heterogeneity. Results Neoadjuvant therapy was not shown to increase the incidence of postoperative AL as demonstrated by an OR of 1.16 (95%CI: 0.99-1.36; P=0.07 [random effect model]). The subgroup analysis of neoadjuvant radiotherapy (nRT) using the random effect model suggested that it did not increase the rate of postoperative AL (OR=1.24; 95%CI: 0.97-1.58; P=0.08). The subgroup analysis of neoadjuvant chemoradiotherapy (nCRT) indicated that the rate of postoperative AL also did not increase with an OR=1.06 (95%CI: 0.86-1.30; P=0.59 [random effect model]). The interval, to surgery after neoadjuvant therapy and preoperative radiotherapy (short- or long-course) were not associated with an increased incidence of postoperative AL. Conclusion Neoadjuvant therapy does not appear to increase the incidence of postoperative AL after anterior resection for mid and low rectal cancer. In addtion, neither the interval to surgery after neoadjuvant therapy nor the radiotherapy regimen increases the rate of postoperative AL. This article is protected by copyright. All rights reserved.