FLT3 ITD
General Information
Lab Name
FLT3
Lab Code
FLT3
Epic Name
FLT3 ITD Mutation DNA Screen
Description
In our PCR assay, purified genomic DNA is amplified using flanking primers and then size fractionated by capillary electrophoresis. For positive patients, a FLT3 ITD to wild type allelic ratio is calculated and reported.
This test should be performed on AML patients at diagnosis. FLT3 mutations tend to be unstable and can change with relapse, so this assay is not a reliable method for detecting minimal residual disease in AML.
A mutation in the FLT3 gene on chromosome 13 results from internal tandem duplications (ITD) in exons 14 and 15 of the juxtamembrane portion of the gene and causes activation of the FLT3 protein. Approximately 20-30% of patients with acute myeloid leukemia have this mutation which has been associated with adverse prognosis.
Please complete a Hematopathology test request form found at Request Form
Analytical Sensitivity/Limit of Detection: signal ratio of 0.0035 ITD
Precision near LOD (CV): 5%
Synonyms
Acute Myeloid Leukemia, AML, FLT, FLT 3, FLT-3, FLT3-ITD, FLT3ITD, FMS-like tyrosine kinase 3, Internal Tandem Duplication, ITD
Components
| Code | Name |
|---|---|
| FLTSD | FLT3 Specimen Description |
| FLTRES | FLT3 Result |
| FLTSIZ | FLT3 ITD Length |
| FLTARO | FLT3 ITD to Normal Ratio |
| FLTINT | FLT3 Interpretation |
| FLTMTH | FLT3 Method and Information |
| FLTGRN | FLT3 Case Number |
Interpretation
Method
PCR amplification of the juxtamembrane portion of the FLT3 gene. Specific for internal tandem duplication mutations
Reference Range
See individual components
Ref. Range Notes
Not applicable
Guidelines
Ordering & Collection
Specimen Type
Collection
Preferred:
Blood: 6mL in Lavender Top (EDTA)
Bone Marrow: 1-2mL in Lavender Top (EDTA)
Tissue, Fluids or Sorted cells: Sterile container in RPMI
Slides: 10 unstained
Accepted:
Green Tops (Heparin), while green tops are accepted for testing, there is documentation that heparin can interfere with some PCR assays.
Extracted DNA will only be accepted from CLIA certified laboratories.
Tissue from stained or cover-slipped slides
Unacceptable:
Specimens received beyond stability limit.
Specimens with low volume or inadequate WBC
Formalin-fixed paraffin embedded tissue (FFPE/PET)
Decalcified or unacceptable fixatives
Forms & Requisitions
Handling Instructions
- Deliver samples to Hematopathology as soon as possible.
- If sample is older than 48 hours, please store at 2-6°C upon receipt and send refrigerated.
- Samples stored at room temperature or refrigerated older than 7 days will be rejected.
- Frozen samples should be shipped on dry ice.
Quantity
requested: Blood: 6mL EDTA/BMA: 1-2mL EDTA/Slides: 10 unstained
minimum: Blood: 1mL EDTA/ BMA: 0.5mL EDTA/ Slides: 5 slides
Processing
Send specimens to Hematopathology – Molecular department for processing.
The stability limit for Blood and Bone Marrow is 7 days, samples beyond this limit will be rejected.
Performance
LIS Dept Code
Molecular Hematopathology (MHP)
Performing Location(s)
| Other |
Hematopathology, Molecular
206-606-7060 UW Hematopathology Laboratory, G7-800 |
Hematopathology, Molecular hours: |
|---|
Frequency
Testing daily Monday - Saturday, results available within 24hrs. EVALHD reflexed or add-on orders may take up to 5 days to complete.
Available STAT?
No