FLT3/NPM1 Mutation Analysis with Interpretation
Label Mnemonic: | FLT3BM |
Epic code: | LAB7865 |
Order form: | Comprehensive Hematopathology Requisition |
Supply order: | Supply Order Form |
Billing: | Billing Policies |
CPT code: | 81245, 81246, 81310 |
Specimen(s):
Bone Marrow
Collection Medium:
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Pink top tube 6 mL (K2-EDTA) |
Minimum:
3 mL bone marrow
Specimens for which the AML blast count is at least 10% will be tested.
Testing on smaller volumes may be attempted. However, this may compromise the ability to perform testing. Testing requires a dedicated collection tube.
Specimens for which the AML blast count is at least 10% will be tested.
Testing on smaller volumes may be attempted. However, this may compromise the ability to perform testing. Testing requires a dedicated collection tube.
Testing Schedule:
0800-1700 Testing offered once per week excluding weekends and
University holidays.
Reference Range:
Expected PCR fragment sizes for each DNA target are provided below for unaffected and affected samples. The vast majority of affected persons harboring one or more of these mutations are heterozygous, meaning both products are present at the diagnostic locus. Unaffected Affected (negative) (positive) FLT3-ITD: 330 bp >330 bp FLT3-D835: 67 bp 197 bp NPM1: 426 bp 430 bp
Comments:
FLT3 and NPM1 Mutation Detection Assays test for two different
mutations in the FLT3 gene and an insertion in exon 12 of the NPM1
gene, all of which are somatic mutations associated with acute
myelogenous leukemia (AML). These molecular markers are useful in
diagnosis and clinical stratification of AML patients.
Detection of FLT3 in-frame internal tandem duplications (FLT3-ITD
mutation) is performed as a mail-out test (sent to a reference
laboratory), whereas the assays that detect FLT3 point mutations
that alter the aspartic acid at position 835 (FLT3-D835) and the
NPM1 mutations are performed in the University of Iowa Molecular
Pathology Laboratory.
To avoid confusion, the results for all 3 targets are reported
together in a consolidated interpretation.
Methodology:
Multiplex PCR followed by Eco RV digestion with fluorescent fragment
analysis on the ABI 3130 (capillary electrophoresis).
Instructions:
Testing is generally not available on a STAT basis. However,
expedited testing can be arranged by contacting the Molecular
Pathology Laboratory at 384-9568 or the Molecular Genetic Pathology
Fellow (pager #8682).
Sample Processing:
Label transport tube with two patient identifiers, date and time of
collection.
Patient's age and sex is required on requisition for processing.
Relevant clinical information must be submitted with specimen in order to provide correct interpretation of test results.
Do Not Centrifuge.
Patient's age and sex is required on requisition for processing.
Relevant clinical information must be submitted with specimen in order to provide correct interpretation of test results.
Do Not Centrifuge.
Sample Storage:
Room temperature for up to 24 hours, then refrigerate the bone
marrow if it is necessary to be held overnight, or weekends, or
holidays.
Transport Instructions:
Place requisition into outside pocket of bag.
Recommend early AM overnight shipping or equivalent if not on courier service.
Ship refrigerated.
Recommend early AM overnight shipping or equivalent if not on courier service.
Ship refrigerated.