Abstract
Background: The outcome of acute myeloid leukemia (AML) is influenced by ethnicity, geographic variations, and the patient's molecular profile. We aimed to explore the mutation frequencies of the nucleophosmin 1 (NPM1) and the FMS-like tyrosine kinase 3 (FLT3) internal tandem duplication (ITD) or tyrosine kinase domain (TKD) with correlation to the cytogenetic profiles in patients with AML.Methods and Results: Bone marrow/whole blood samples from 33 patients with AML were screened for NPM1/FLT3-ITD mutations by fragments analysis using a GeneScan analyzer. Depending on the fragment size, the NPM1 and FLT3 wild type (Wt) (170 bp and 330 bp) vs. mutated (170/174 bp and 330/351 bp) alleles, respectively, can be distinguished. The allelic ratio of FLT3-ITD+ was calculated. FLT3-TKD+ mutation was detected by Sanger sequencing. Samples were tested for chromosomal aberrations. According to the French-American-British (FAB) classification, the predominant type in the present cohort was AML-M5, accounting for 30.3%. NPM1+, FLT3-ITD+, and double mutations were found in 12.1%, 3.1%, and 6.1% of cases, respectively. The combined NPM1+/FLT3-ITD+/FLT3-TKD+ profile was presented in one patient (3.1%). The dual positivity group (NPM1+/FLT3+) significantly had a higher WBC count with a median of 81.3x103/mu L. A total of 63.6% of patients had abnormal cytogenetics. The NPM1+/FLT3-ITD+ patients had normal karyotypes. Patients with NPM1-/FLT3- showed complex karyotype (24%) and t(8;21) (8%). The FLT3-ITD+patient had trisomy 8.Conclusion: The frequency ofNPM1/FLT3 mutations in the study cohort showed less rate than in other studies with a distinct pattern. Due to the preliminary nature of the present work, more extensive screening is warranted to evaluate their usefulness as prognostic indicators in this region.