Published online Nov 21, 2015. doi: 10.3748/wjg.v21.i43.12234
Peer-review started: May 8, 2015
First decision: August 31, 2015
Revised: September 5, 2015
Accepted: October 23, 2015
Article in press: October 26, 2015
Published online: November 21, 2015
Core tip: Irinotecan is a key anticancer drug for the treatment of metastatic colorectal cancer. By combining irinotecan with 5-fluorouracil, oxaliplatin, and a molecularly-targeted drug, overall survival of longer than 30 mo has been achieved. Exposure to SN-38, the active metabolite of irinotecan, shows large inter- and intra-patient variability and can cause severe irinotecan-related toxicities. Many studies have recommended the dose reduction of irinotecan for patients with UDP-glucuronosyltransferase 1A1 polymorphisms and liver dysfunction. Surprisingly, dose reduction may be required in patients with severe renal failure, even though irinotecan is predominantly eliminated via the liver.