UGT1A1 Irinotecan Toxicity

CPT: 81350
Print Share

Synonyms

  • Camptosar®
  • Irinotecan

Expected Turnaround Time

5 - 7 days


Related Documents


Specimen Requirements


Specimen

Whole blood or LabCorp buccal swab kit (buccal swab collection kit contains instructions for use of a buccal swab)


Volume

5 mL whole blood or LabCorp buccal swab kit


Minimum Volume

3 mL whole blood or two buccal swabs


Container

Lavender-top (EDTA) tube, yellow-top (ACD) tube, or LabCorp buccal swab kit


Collection

Whole blood preferred. Collect specimen in a lavender-top (EDTA) or yellow-top (ACD) tube, or use a buccal swab kit. Ship whole blood specimen at room temperature or frozen. Ship buccal swab collection kit at room temperature.


Storage Instructions

Maintain whole blood specimen at room temperature for 7 days or refrigerated for 1 month, or frozen for 2 years. Maintain buccal swabs at room temperature for 6 months.


Stability Requirements

Temperature

Period

Room temperature

Whole blood: 7 days; buccal swab: 6 months

Refrigerated

Whole blood: 1 month

Frozen

Whole blood: 2 years


Causes for Rejection

Hemolysis; quantity not sufficient for analysis; improper container; single buccal swab; wet buccal swab


Test Details


Use

Irinotecan (Camptosar®) is used, or under evaluation, in a broad spectrum of solid tumors, and is often prescribed for treating patients with metastatic cancer of the colon or rectum, especially when 5-fluorouracil treatment has not been entirely successful. Severe toxicity (eg, grade 4 neutropenia) is commonly observed in cancer patients receiving irinotecan who carry the UGT1A1*28 allele, also called TA. This test result will provide valuable information to physicians prior to initiating or modifying treatment or supplementing treatment with additional drugs.

UGT1A1 variants have also been reported in patients with disorders of bilirubin metabolism, such as Crigler-Najjar Types I and II, as well as Gilbert syndrome. Between 80% to 100% of Caucasian patients with Gilbert syndrome are reported to have either one or two copies of UGT1A1*28. G71R (*6), a UGT1A1 variant reported in Asian patients with Gilbert syndrome, is not detected by this assay.


Limitations

The current test will only test the TATA box polymorphism of the UGT1A1 gene. The other polymorphisms of this gene will not be detected.

This test was developed, and its performance characteristics determined, by LabCorp. It has not been cleared or approved by the US Food and Drug Administration (FDA).


Methodology

Polymerase chain reaction (PCR); capillary electrophoresis


References

Beutler E, Gelbart T, Demina A. Racial variability in the UDP-glucuronosyltransferase 1 (UGT1A1) promoter: a balanced polymorphism for regulation of bilirubin metabolism? Proc Natl Acad Sci USA. 1998 Jul; 95(14):8170-8174. 9653159
Innocenti F, Undevia SD, Iyer L, et al. Genetic variants in the UDP-glucuronosyltransferase 1A1 gene predict the risk of severe neutropenia of irinotecan. J Clin Oncol. 2004 Apr 15, 22(8):1382-1388. 15007088
Rouits E, Boisdron-Celle M, Dumont A, Guérin O, Morel A, Gamelin E. Relevance of different UGT1A1 polymorphisms in irinotecan-induced toxicity: A molecular and clinical study of 75 patients. Clin Cancer Res. 2004 Aug 1; 10(15):5151-5159.15297419

LOINC® Map

Order Code Order Code Name Order Loinc Result Code Result Code Name UofM Result LOINC
511200 UGT1A1 Irinotecan Toxicity 41044-9 511202 Result: 41044-9
511200 UGT1A1 Irinotecan Toxicity 41044-9 511224 Additional Information: N/A
511200 UGT1A1 Irinotecan Toxicity 41044-9 511208 Director Review: 72486-4
511200 UGT1A1 Irinotecan Toxicity 41044-9 000000 MGRM Informed Consent Review N/A

For Providers

Please login to order a test

Order a Test

© 2021 Laboratory Corporation of America® Holdings and Lexi-Comp Inc. All Rights Reserved.

CPT Statement/Profile Statement

The LOINC® codes are copyright © 1994-2021, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee. Permission is granted in perpetuity, without payment of license fees or royalties, to use, copy, or distribute the LOINC® codes for any commercial or non-commercial purpose, subject to the terms under the license agreement found at https://loinc.org/license/. Additional information regarding LOINC® codes can be found at LOINC.org, including the LOINC Manual, which can be downloaded at LOINC.org/downloads/files/LOINCManual.pdf