FLT3 Mutational Analysis, PCR

Indication

Detection of activating mutations in the receptor tyrosine kinase FLT3 that occur in 15% of acute myeloid leukemia. The mutations include an internal tandem duplication (ITD) in the juxtamembrane domain coding sequence and a missense mutation in the kinase domain (D835) of the FLT3 gene that impart a poor prognosis.

To select AML cases that are appropriate for targeted therapy.

Methodology

A fluorescent-based PCR is used to detect ITD and D835 point mutations in Flt3 using DNA isolated from bone marrow or peripheral blood. Flt3/ITD is assessed by amplification of the JM domain using primers from exons 14 and 15. Mutations at D835 are assessed by restriction fragment length polymorphism mediated assay using primers flanking the mutation site.

Test Parameters

This assay will detect internal tandem duplications (ITD) in the juxtamembrane domain and point mutations in codons 835 and 836. The sensitivity of the test is approximately one cell with mutated FLT3 in 20-100 total cells (1-5%).

Turnaround Time

Four to six working days

Sample Requirements

• 10 ml peripheral blood in purple top tube (EDTA Vacutainer), sent on wet ice
  
  or
  
• 2-5 ml of bone marrow aspirate, sent on wet ice

Note: This test is only available for patients seen by physicians at MD Anderson Cancer Center.

CPT Codes

81245, 81479

The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.