Bi-directional sequencing of the exon 4 mutation hotspot regions in both the IDH1 and IDH2 genes. IDH1 and IDH2 are analyzed concurrently. In hematological disease, testing may be performed on plasma to increase sensitivity. For solid tumors, tumor enrichment is performed before extraction.
IDH1 or IDH2 mutations are detected in approximately 15-20% of acute myeloid leukemia (AML) and >70% grade II or III brain gliomas. Patients with AML and mutations are likely to have aggressive disease, while mutations in gliomas are associated with better prognosis. Long-term survival after aggressive tumor resection has been reported for patients with IDH1-positive astrocytomas.
- Peripheral blood: 5 mL in EDTA tube.
- Bone marrow: 2 mL in EDTA tube.
- FFPE solid tumor tissue: Paraffin block is preferred. Alternatively, send 1 H&E slide plus 5-10 unstained slides cut at 5 or more microns. Please use positively-charged slides and 10% NBF fixative. Do not use zinc fixatives.
Use cold pack for transport, making sure cold pack is not in direct contact with specimen. Slides can be packed at room temperature.