Identification of codon 132 mutation in the IDH1 gene and codon 140 and 172 mutations in the IDH2 gene
Performing Laboratory / Facility
UCLA Medical Center Clinical Laboratory (CHS)
Performing Section
Molecular Pathology
Availability
Monday through Friday, 0700-1700
Turnaround Time
5 days from receipt of specimen in performing lab
Methodology
Sequencing analysis. Polymerase chain reaction (PCR) is performed for DNA amplification. Primers are designed specifically for the region surrounding codon 172 of the IDH2 gene. PCR products are sequenced and analyzed on the ABI 3730xl Genetic Analyzer.
Reflex Testing IDH2 Mutation Detection is available as a reflex test. See algorithm:
Initial Test
Criteria for Reflex
Reflexes To
Reflex Billing CPT Code
IDH1 Mutation Analysis (CPT code 81403)
Negative
IDH2 Mutation Analysis
81403
Use
Mutations in codon 132 of IDH1 and codon 172 of IDH2 have collectively been found in 60% to 90% of low grade astrocytomas and oligodendrogliomas, as well as in secondary glioblastomas that developed from these tumors, and are associated with a better prognosis. However, other tumor types have also been found to carry IDH1 mutations in codon 132 and IDH2 mutations in codon 172 where the prognostic implications are still unclear, including acute myeloid leukemias, rare prostate carcinomas, and a few B-cell acute lymphoblastic leukemias.
Limitations
The provided tumor tissue should be composed of >=40% tumor cells for accurate test interpretation. Preparation of DNA from tissue samples is dependent on the quality of the specimen provided. Inadequate DNA extraction may occur in a significant number of paraffin-embedded specimens. This assay can detect approximately 15% to 20% of mutant in a background of wild-type genomic DNA. At lower proportions in a mixed specimen, they will not be reliably detected.
Specimen Type
Whole Blood Bone Marrow
Container
Lavender/EDTA
Volume
Whole Blood - 4mL Bone Marrow - 4 mL
Minimum Volume
Whole Blood - 1mL Bone Marrow - 1 mL
Shipping and Handling Instructions
Transport specimen at room temperature.
Causes for Rejection
Tumor block containing insufficient tumor tissue Tumor tissue fixed in a heavy metal fixative (eg, B-5 or Zenker's fixatives), Broken and stained slides
Reference Range
No mutation observed
Test Information
CPT Codes
81120 81121
Test Includes
Identification of codon 132 mutation in the IDH1 gene and codon 140 and 172 mutations in the IDH2 gene
Performing Laboratory / Facility
UCLA Medical Center Clinical Laboratory (CHS)
Performing Section
Molecular Pathology
Availability
Monday through Friday, 0700-1700
Turnaround Time
5 days from receipt of specimen in performing lab
Methodology
Sequencing analysis. Polymerase chain reaction (PCR) is performed for DNA amplification. Primers are designed specifically for the region surrounding codon 172 of the IDH2 gene. PCR products are sequenced and analyzed on the ABI 3730xl Genetic Analyzer.
Reflex Testing IDH2 Mutation Detection is available as a reflex test. See algorithm:
Initial Test
Criteria for Reflex
Reflexes To
Reflex Billing CPT Code
IDH1 Mutation Analysis (CPT code 81403)
Negative
IDH2 Mutation Analysis
81403
Use
Mutations in codon 132 of IDH1 and codon 172 of IDH2 have collectively been found in 60% to 90% of low grade astrocytomas and oligodendrogliomas, as well as in secondary glioblastomas that developed from these tumors, and are associated with a better prognosis. However, other tumor types have also been found to carry IDH1 mutations in codon 132 and IDH2 mutations in codon 172 where the prognostic implications are still unclear, including acute myeloid leukemias, rare prostate carcinomas, and a few B-cell acute lymphoblastic leukemias.
Limitations
The provided tumor tissue should be composed of >=40% tumor cells for accurate test interpretation. Preparation of DNA from tissue samples is dependent on the quality of the specimen provided. Inadequate DNA extraction may occur in a significant number of paraffin-embedded specimens. This assay can detect approximately 15% to 20% of mutant in a background of wild-type genomic DNA. At lower proportions in a mixed specimen, they will not be reliably detected.
Specimen Collection and Handling
Specimen Type
Whole Blood Bone Marrow
Container
Lavender/EDTA
Volume
Whole Blood - 4mL Bone Marrow - 4 mL
Minimum Volume
Whole Blood - 1mL Bone Marrow - 1 mL
Shipping and Handling Instructions
Transport specimen at room temperature.
Causes for Rejection
Tumor block containing insufficient tumor tissue Tumor tissue fixed in a heavy metal fixative (eg, B-5 or Zenker's fixatives), Broken and stained slides
