Risk of irinotecan toxicity by genotype*
*Based on data from Br J Cancer 2004; 91:678-82.
Irinotecan (CPT-11) is a common chemotherapeutic drug used for the treatment of advanced colorectal and gastric cancer. Allelic variance of UGT1A1 may be associated with increased drug toxicity and with syndromes such as Gilbert syndrome (benign familial hyperbilirubinemia) and Crigler-Najjar (rare form of nonhemolytic jaundice).
Tests generally appear in the order most useful for common clinical situations
|Test name: UDP Glucuronosyltransferase 1A1 (UGT1A1) Genotyping|
|ARUP #: 0051332|
|Methodology: Polymerase Chain Reaction/Fragment Analysis|
Identify patients at risk for toxicity associated with irinotecan and related drugs
Test to confirm Gilbert syndrome
Variations in the UGT1A1 gene, other than those targeted, will not be detected
Clinical significance of the rare (TA)5 and (TA)8 alleles on risk of irinotecan toxicities is not well established
Genetic and nongenetic factors other than UGT1A1 may contribute to irinotecan toxicity and efficacy