Detection of internal tandem duplication and exon 20 tyrosine kinase domain (TKD) mutations using fragment-length analysis or a combination of fragment-length analysis and bi-directional sequencing. Positive results identify specific TKD mutations or report ITD results quantitatively as allelic ratio. Testing may be performed on plasma to increase sensitivity.
Testing for FLT3 and other gene mutations in AML patients with intermediate-risk cytogenetic abnormalities can improve risk stratification. The presence of an FLT3 mutation in a patient with AML implies aggressive disease.
- Peripheral blood: 5 mL in EDTA tube.
- Bone marrow: 2 mL in EDTA tube.
- FFPE 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.