The efficacy of irinotecan supplementation for colorectal cancer: A meta-analysis of randomized controlled studies

Background: The efficacy of irinotecan as the adjunctive therapy to fluorouracil and leucovorin remains controversial in patients with colorectal cancer. We conduct this meta-analysis to explore the efficacy of irinotecan supplementation for colorectal cancer. Methods: We have searched PubMed, EMBASE, Web of science, EBSCO, and Cochrane library databases through March 19, 2020, and included randomized controlled trials assessing the efficacy of irinotecan plus fluorouracil and leucovorin for colorectal cancer. Results: Five randomized controlled trials were included in the meta-analysis. Compared with fluorouracil and leucovorin for colorectal cancer, irinotecan supplementation could significantly improve progression-free survival rate (hazard ratio = 0.72; 95% confidence interval [CI] = 0.58-0.90; P = .003), median progression-free survival (standard mean difference = -0.30; 95% CI = -0.44 to -0.15; P < .0001), overall survival rate (hazard ratio = 0.77; 95% CI = 0.66-0.90; P = .001), and objective response (risk ratio [RR] = 0.57; 95% CI = 0.49-0.66; P < .00001) and decrease progressive disease (RR = 2.10; 95% CI = 1.40-3.14; P = .0003), but revealed no obvious effect on complete response (RR = 0.88; 95% CI = 0.33-2.29; P = .79). The incidence of grade >= 3 adverse events in irinotecan supplementation group was increased compared to control group (RR = 0.67; 95% CI = 0.57-0.79; P < .00001). Conclusions: Irinotecan as the adjunctive therapy to fluorouracil and leucovorin can increase the survival and objective response of patients with colorectal cancer, but the incidence of grade >= 3 adverse events is found to be increased after irinotecan supplementation.