Determination of FLT3-ITD and D835Y mutations as a factor of prognosis in immunophenotypically verified diagnosis of patients with acute myeloid leukemia in Saint Petersburg
Konstantin U. Slobodnyuk, Irina Y. Saburova, Margarita V. Gorchakova, Ekaterina B. Rusanova, Antonina V. Kurtova, Mikhail I. Zaraiski, Yekaterina E. Zueva
Department of Clinical Laboratory Diagnostics, Center for Laboratory Diagnostics, St. Petersburg Pavlov State Medical University,
St. Petersburg, Russia
Summary
Purpose
Multicolor flow cytometry has been the “gold standard” in diagnostics of Acute Myeloid Leukemia (AML) since 1995. Different types of AML are associated with different cytogenetic abnormalities, but 40–60% of patients with AML are not determined. FLT3-ITD and D835Y mutations – which are associated with an extremely unfavorable prognosis of AML – have been identified in 20–30% of AML patients with normal karyotypes. The aim was to study a diagnostic significance of detecting FLT3-ITD and D835Y mutations in patients with verified diagnoses of AML.
Materials
The study included 33 patients of St. Petersburg. To verify the diagnosis of AML, we used the method of multicolor flow cytometry (Cytomics FC500, Beckman Coulter), as well as morphology, cytochemistry, and clinics. For the molecular genetic studies of FLT3-ITD and D835Y mutations, we used the standard method of PCR analysis for detection with a double primer scheme of results in a polyacrylamide gel.
Results
Cytogenetic abnormalities were identified among 11 AML patients (33%). In 8 patients (24%) diagnosed with AML, the FLT3-ITD mutation was detected, including the cases with AML M0 (n=1), AML M0-M1 (n=1), AML M2 (n=3), AML M3 (n=1), and AML M4 (n=2). In 25 patients with clinical, immunophenotypic, and morphological verified diagnosis, the mutation is not defined. In only 3 patients (9%) with AML was the D835Y mutation detected, but without the FLT3-ITD mutation including cases with AML M2 (n=1), AML M3 (n=1), AML M4 (n=1).
Summary
Investigation of FLT3-ITD and D835Y mutations may be recommended for inclusion to the standard of diagnosis of acute myeloid leukemia.
Keywords
acute myeloid leukemia, FLT3-ITD, D835Y, mutation, flow cytometry, prognosis
