Cytogenetics and molecular markers of acute myeloid leukemia from a tertiary care center in Saudi Arabia

Abstract

Background/Purpose: Acute myeloid leukemia (AML) is a phenotypically and genetically heterogeneous disease. This heterogeneity is attributed to alterations in genetic bases. AML classification based on these abnormalities is essential for accurate diagnosis, risk stratification, prognostic value, monitoring of minimal residual disease, and developing targeted therapies. This study evaluates frequency of each karyotype and molecular abnormality at our institution with comparison to other international studies. Materials and Methods: We reviewed 100 bone marrow samples, which represent all AML diagnosed cases at our hospital from 2012 to 2014 by conventional karyotyping, specific AML–FISH panel, and variety of AML-specific mutations using Sanger sequencing. Results: Out of 100 AML patients investigated with median age of 29 years, 98 were successfully karyotyped, and 64% of cases had an abnormality. In addition, all 100 AML–FISH panel and molecular studies were informative with an abnormality reaching 50 and 45%, respectively. Conventional and molecular cytogenetic studies revealed trisomy 8 (15%), t(8;21) in 12%, trisomy 21(8%), inv(16) in 7%, t(15;17) in 6%, 11q rearrangements (6%), and inv(3) in 2%. The mutational analysis showed nucleophosmin 1 (12%), FMS-like tyrosine kinase-3–internal tandem duplication (9%), IDH2 (7%), IDH1 (6%), WT1 (5%), DNMT3A (4%), CEBPA (4%), and c-KIT (3%). Conclusion: The incidence of most mutational analysis is lower, whereas abnormal karyotype showed almost similar frequency when compared to different international centers. This is the first cytogenetic data from Saudi Arabia for AML, including all these genetic mutations. Therefore, a multicenter collaboration and comprehensive study is recommended to confirm these findings.