Test Code

M FLT3*

Test Synonyms

FLT3 gene, ITD mutation

Associations

Acute myelogenous leukemia (AML)

Reflex testing

Methodology

*Performed by affiliate laboratory.

Turnaround Time

10-14 days

Specimen Requirements

5.0 mL (min. 3.0 mL) whole blood or (min. 2.0 mL) bone marrow EDTA, Sodium Heparin or ACD

Specimen Stability

Storage & Handling

Ship at ambient temperature, cool in summer. (Do not allow cool/refrigerated pack to directly contact sample.)

Causes for Rejection

Improper specimen labeling; Insufficient sample volume; Clotted specimen; Specimen older than 7 days

Reference Range

Internal tandem duplication (ITD) or missense (D835) mutations detected / not detected

Description

Intended for use as a screening test in patients with AML to assist with stratification and selection of post-remission therapies.

Internal tandem duplications in exons 14 and 15 of the FMS-related tyrosine kinase 3 (FLT3) gene are found in ~30% of cytogenetically normal AML patients. The duplications result in an abnormally active protein that promotes proliferation and survival of leukemic cells. FLT3 mutations are associated with a poor prognosis.

References

1. Acute myeloid leukemia, NCCN clinical practice guidelines in oncology (2008).
2. Mrozek K et al. (2007). Clinical relevance of mutations and gene-expression changes in adult acute myeloid leukemia with normal cytogenetics: are we ready for a prognostically prioritized molecular classification? Blood. 109:431-448.
3. Meshinchi S et al. (2006). Clinical implications of FLT3 mutation in pediatric acute myeloid leukemia. Blood. 108(12):3654-3661.
4. Kiyoi H and Naoe T. (2006). Biology, clinical relevance, and molecularly targeted therapy in acute leukemia with FLT3 mutation. Int J Haematol. 83(4):301-308.
5. Fohling S et al. (2005). Genetics of myeloid malignancies: pathogenetic and clinical implications. J Clin Oncol. 23(26):6285-6295.
6. Kiyoi H et al. (2005). Clinical significance of FLT3 in leukemia. Int J Haematol. 82(2):85-92.
7. Yamamoto Y et al. (2001). Activating mutation of D835 within the activation loop of FLT3 in human hematologic malignancies. Blood. 97(8):2434-2439.