Evaluation of Cytogenetic Changes and FLT3 mutations in Patients with Acute Promyelocytic Leukemia

Abstract

Introduction: The secondary genetic changes other than the PML-RARA fusion gene may contribute to the acute promyelocytic leukemogenesis. Chromosomal alterations and mutation of FLT3 tyrosine kinase receptor are the frequent genetic alterations in acute myeloid leukemia (AML). However, the prognostic significance of FLT3 mutations in acute promyelocytic leukemia (APL) is not firmly established.
Patients & Methods: FLT3 ITD screening by fragment length analysis and FLT3 D835 mutation by melting curve analysis in 23 APL samples was screened in this study.
Results: About13% of the patients had FLT3 internal tandem duplications (ITDs), and 26% had D835 point mutation. FLT3 ITD mutation was associated with higher white blood cell (WBC) count at presentation and poor prognosis.
Conclusions: As the PML-RARA is not sufficient to develop APL, we assume FLT3 mutations and additional chromosomal alterations in this APL series may cooperate with PML-RARA in APL development.