Association between UGT1A1*28 Gene Polymorphism and Severe Neutropenia due to Colorectal Cancer Treatment with Irinotecan: Evidence Based on Meta-Analysis

Objective The present study aimed to evaluate the relationship between UGT1A1*28 gene polymorphism and the prevalence of neutropenia in patients with colorectal cancer treated with irinotecan. Method Thirteen studies were included. These papers were selected from the Virtual Health Library, Scientific Electronic Library Online, International Health Sciences Literature and PubMed, and their data were collected and evaluated using the BioEstat 5.3 software (BioEstat, Belém, PA, Brazil). Results Three genotypes were analyzed, namely 6/6 (wild type), 6/7, and 7/7. In total, 2,146 patients were included in the present study; of these, 55.6% (n = 1,193) had 6/6 genotype, 37.3% (n = 801) were heterozygous (6/7), and 7.1% (n = 152) had the 7/7 genotype. A total of 1,672 (77.9%) patients displayed mild neutropenia, whereas 474 (22.1%) had severe neutropenia. When contrasting the 6/7 and 7/7 genotypes with the 6/6 genotype using statistical tests for meta-analysis, patients with the 7 allele, either in homozygosis or heterozygosis, presented higher risk of developing severe neutropenia than patients with the 6/6 genotype (odds ratio = 1.559; 95% confidence interval = 1.163–2.090; p = 0.003). Conclusion The analysis of the UGT1A1*28 gene polymorphism can aid the choice of treatment for patients with colorectal cancer in personalized medicine, increasing the chances of therapeutic success