UGT1A1 genotyping in the second-line treatment of colorectal cancer with high-dose Irinotecan administered once every 3 weeks, along with adjusting the initial Irinotecan dose for patients with the UGT1A1-7/7 genotype, resulted in cost savings for African and Caucasian populations. This evidence concerns the gene UGT1A1 and colorectal cancer.