Ordering Recommendation

Identify the most common IDH mutation in diffuse gliomas. Negative results reflexes to IDH1 and IDH2 Mutation Analysis, Exon 4 (2006444) to assess for less common IDH mutations.

Mnemonic

IDH1 RFLX

Methodology

Immunohistochemistry

Performed

Mon-Fri

Reported

1-5 days, add 8-14 days if reflexed

New York DOH Approval Status

This test is New York DOH approved.

Specimen Required

Patient Preparation
Collect

Tumor tissue.

Specimen Preparation

Formalin fix (10 percent neutral buffered formalin is preferred) and paraffin embed specimen. Protect paraffin block and/or slides from excessive heat. Transport tissue block or 7 unstained (5-micron thick sections), positively charged slides in a tissue transport kit (ARUP supply #47808) available online through eSupply using ARUP Connect™ or contact ARUP Client Services at (800)522-2787. (Min. 4 slides) If sending precut slides, do not oven bake.

Storage/Transport Temperature

Room temperature. Also acceptable: Refrigerated. Ship in cooled container during summer months.

Unacceptable Conditions

Paraffin block with less than 25 percent tumor tissue. Specimens fixed/processed in alternative fixatives (alcohol, Prefer) or heavy metal fixatives (B-4 or B-5). Decalcified specimens.

Remarks

Include surgical pathology report.
If multiple specimens (blocks or slides) are sent to ARUP, they must be accompanied by one of the following: an order comment indicating that the ARUP pathologist should choose the specimen most appropriate for testing (e.g., "Choose best block"), or individual orders for each sample submitted. A Pathologist Block Selection Fee (ARUP test code 3002076) will be added to orders that utilize the first option. If multiple specimens are sent to ARUP without a request for pathologist block/slide selection or individual orders, they will be held until clarification is provided.

Stability

Ambient: Indefinitely; Refrigerated: Indefinitely; Frozen: Unacceptable

Reference Interval

Interpretive Data

Refer to report.

Compliance Category

Laboratory Developed Test (LDT)

Note

This test code includes pathologist interpretation.

Negative IHC results will reflex to IDH1 and IDH2 Mutation Analysis, Exon 4, to assess for less common IDH mutations. Additional charges apply.

Hotline History

N/A

CPT Codes

88342, if reflexed add 88381; 81120; 81121

Components

Component Test Code* Component Chart Name LOINC
2002148 Block ID 57723-9
3002136 IDH1 R132H Point Mut by IHC with Reflex
3003120 IDH1 Tissue Source
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.

Aliases

  • Astrocytoma and Oligodendroglioma Tumor Cell Marker
  • IDH1 Point mutation IHC
  • IDH1 R132H antibody staining
  • IDH1 R132H IHC, Isocitrate dehydrogenase
IDH1 R132H Point Mutation by Immunohistochemistry with Reflex to IDH1 and IDH2 Mutation Analysis, Exon 4