Test Code IDHT IDH1 and IDH2 Mutation Analyses, Next-Generation Sequencing, Tumor
Ordering Guidance
If this test is ordered with TERTD / TERT Promoter Mutation Analysis, Droplet Digital PCR, Tumor, this test will be canceled and IDTRT / IDH1, IDH2, and TERT Mutation Analysis, Next-Generation Sequencing, Tumor will be ordered.
Multiple oncology (cancer) gene panels are available. For more information see Hematology, Oncology, and Hereditary Test Selection Guide.
Necessary Information
A pathology report (final or preliminary), at minimum containing the following information, must accompany specimen for testing to be performed:
1. Patient name
2. Block number-must be on all blocks, slides, and paperwork (can be handwritten on the paperwork)
3. Tissue collection date
4. Source of the tissue
Specimen Required
This assay requires at least 20% tumor nuclei.
-Preferred amount of tumor area with sufficient percent tumor nuclei: tissue 216 mm(2)
-Minimum amount of tumor area: tissue 36 mm(2)
-These amounts are cumulative over up to 10 unstained slides and must have adequate percent tumor nuclei.
-Tissue fixation: 10% neutral buffered formalin, not decalcified
-For specimen preparation guidance, see Tissue Requirements for Solid Tumor Next-Generation Sequencing. In this document, the sizes are given as 4 mm x 4 mm x 10 slides as preferred: approximate/equivalent to 144 mm(2) and the minimum as 3 mm x 1 mm x 10 slides: approximate/equivalent to 36 mm(2).
Preferred: Submit 3, if available, or 2 of the following specimens
Acceptable: Submit at least one of the following specimens.
Specimen Type: Tissue block
Collection Instructions: Submit a formalin-fixed, paraffin-embedded tissue block with acceptable amount of tumor tissue.
Specimen Type: Tissue slide
Slides: 1 Hematoxylin and eosin-stained and 10 unstained
Collection Instructions:
Submit the followings slides:
1 Slide stained with hematoxylin and eosin
AND
10 Unstained, nonbaked slides with 5-micron thick sections of the tumor tissue.
Note: The total amount of required tumor nuclei can be obtained by scraping up to 10 slides from the same block.
Additional Information: Unused unstained slides will not be returned.
Specimen Type: Cytology slide (direct smears or ThinPrep)
Slides: 1 to 3 Slides
Collection Instructions: Submit 1 to 3 slides stained and coverslipped with a total of 5000 nucleated cells (preferred) or at least 3000 nucleated cells (minimum).
Note: Glass coverslips are preferred; plastic coverslips are acceptable but will result in longer turnaround times.
Additional Information: Cytology slides will not be returned. An image of the slides will be stored per regulatory requirements.
Genetics Test Information
This test uses targeted next-generation sequencing to evaluate for somatic mutations within the IDH1 and IDH2 genes. See Targeted Genes and Methodology Details for IDH1/IDH2 Mutation Analysis for details regarding the targeted gene regions evaluated by this test.
This test is performed to evaluate for somatic mutations within solid tumor samples. It does not assess for germline alterations within the genes listed.
Specimen Type
VariesSpecimen Minimum Volume
See Specimen Required
Specimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
Varies | Ambient (preferred) | |
Refrigerated |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Reference Values
An interpretive report will be provided.
Day(s) Performed
Monday through Friday
Report Available
12 to 20 daysSpecimen Retention Time
Tissue blocks: Unused portions of blocks will be returned; Tissue slides: Unused slides are stored for at least 5 years; Extracted DNA: 3 monthsPerforming Laboratory

CPT Code Information
88381-Microdissection, manual
81479