Purpose: Although 5-aminosalicylates and thiopurines may have an antineoplastic effect on colorectal neoplasia in patients with inflammatory bowel disease (IBD), their impact on the progression of low-grade dysplasia (LGD) in IBD is uncertain. Therefore, we performed a systematic review and meta-analysis to evaluate whether 5-aminosalicylates or thiopurines can protect against the progression of LGD in patients with IBD.
Methods: Systematic searches of PubMed, EMBASE, Cochrane Library databases, and major conference proceedings were conducted to identify all eligible studies through March 2020. Data were pooled using a random effects model. Study quality was assessed using the Newcastle-Ottawa Scale.
Results: Five studies comprising 776 IBD patients with LGD were included. Overall, 5-aminosalicylates (Hazard ratio (HR) = 0.91, 95% confidence interval (CI) 0.55-1.51) and thiopurines (HR = 0.64, 95% CI 0.23-1.79) did not significantly reduce the risk of advanced colorectal neoplasia (high-grade dysplasia/cancer) in IBD patients with LGD. Moreover, the effects of 5-aminosalicylates or thiopurines on risk of advanced colorectal neoplasia in IBD patients with LGD were not significant by different primary sclerosing cholangitis status, study quality, sample size, and IBD type.
Conclusions: In this study, we did not find a significant protective effect of 5-aminosalicylates or thiopurines on the progression of LGD in patients with IBD.
Keywords: 5-Aminosalicylates; Colorectal cancer; Dysplasia; Inflammatory bowel disease; Thiopurines.