Prospective analysis of UGT1A1 promoter polymorphism for irinotecan dose escalation in metastatic colorectal cancer patients treated with bevacizumab plus FOLFIRI as the first-line setting: study protocol for a randomized controlled trial

摘要

Background Irinotecan is approved and widely administered to metastatic colorectal cancer (mCRC) patients; however, it can cause severe toxicities including neutropenia and diarrhea. The polymorphisms of genes encoding drug-metabolizing enzymes can play a crucial role in the increased susceptibility of cancer patients to chemotherapy toxicity. Therefore, we plan to explore the effect of the genetic polymorphism of uridine diphosphate glucuronosyltransferase 1A1 ( UGT1A1 ) for irinotecan detoxification in mCRC patients. This trial will compare the clinical outcomes and side effects observed in mCRC patients treated with bevacizumab plus 5-fluorouracil/leucovorin/irinotecan (FOLFIRI) with and without UGT1A1 genotyping and irinotecan dose escalation. A total of 400 mCRC patients were randomized into a study group and a control group. Methods/Design This trial is a prospective, multicenter, randomized clinical trial comparing UGT1A1 promoter polymorphism for irinotecan dose escalation in mCRC patients administered with bevacizumab plus FOLFIRI as the first-line setting. The enrolled patients were randomly assigned to one of two groups, a study group and a control group, on the basis of receiving UGT1A1 genotyping or not. The study group receive a biweekly FOLFIRI regimen, with irinotecan dose escalation based on UGT1A1 genotyping; whereas the control group receive the conventional biweekly FOLFIRI regimen without UGT1A1 genotyping. The clinicopathological features, response rates, toxicity, and progression-free survival or overall survival will be compared between the two groups. Discussion Patients with mCRC undergoing UGT1A1 genotyping may receive escalated doses of irinotecan for a potentially more favorable clinical response and outcome, in addition to comparable toxicities. Such personalized medicine based on genotyping may be feasible for clinical practice. Trial registration NCT02256800 . Date of registration: 3 October 2014. Date of first patient randomized: 16 January 2015