Isocitrate Dehydrogenase 1 and 2 (IDH1/IDH2) Mutation Analysis

Test Code
31547


CPT Codes
81120, 81121

Preferred Specimen
5 mL whole blood or 3 mL bone marrow collected in an EDTA (lavender-top) tube or sodium heparin (green-top) tube


Minimum Volume
3 mL whole blood • 1 mL bone marrow


Other Acceptable Specimens
500 ng extracted DNA in a leak-proof container • Cell pellet


Instructions
Blood specimens should be shipped immediately after collection. Draw date is required to determine the stability of the sample. Do not reject.

DNA must be from a CLIA approved laboratory. Other sample types by Medical Review Process and Director approval only.

Cell pellet: This assay is also designed for the remnant cell pellet from Cytogenetics. The cell pellet usually fixed should be transported refrigerated to the laboratory as soon as possible. Please provide a copy of the Cytogenetics report.


Transport Temperature
Whole blood and bone marrow: Room temperature
Extracted DNA and cell pellet: Refrigerated (cold packs)


Specimen Stability
Whole blood and bone marrow
Room temperature: 7 days
Refrigerated: 7 days
Frozen: Unacceptable

Extracted DNA
Room temperature: Unacceptable
Refrigerated: 5 years
Frozen: 5 years

Cell pellet
Room temperature: Unacceptable
Refrigerated: 30 days
Frozen: 30 days


Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Gross hemolysis • Clotted


Methodology
Polymerase Chain Reaction (PCR)

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule
Sets up 7 days a week.


Report Available
Reports in 3 to 5 days.


Clinical Significance
IDH1 and IDH2 (Isocitrate dehydrogenase 1 and 2) encode enzymes that catalyzes oxidative decarboxylation of isocitrate into alpha-ketoglutarate (alpha-KG). Gain-of-function mutations in the IDH genes are associated with aberrant conversion of alpha-KG to 2-hydroxyglutarate (2-HG), which is an oncogenic metabolite, and are recurrent in myeloid malignancies and glioma. IDH1 (7-14%) exon 4 and IDH2 exon 4 (8-19%) mutations occur frequently in AML and are found to be associated with unfavorable prognosis and inferior overall survival in some studies. IDH inhibitors have been FDA-approved for IDH-mutated relapsed or refractory acute myeloid leukemia (AML).




The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.