Cytogenetic Profile of de novo Acute Myeloid Leukemia Patients in Malaysia

Acute myeloid leukemia (AML) is a heterogeneous disease in terms of cytogenetics and molecular genetics. AML is the most common acute leukemia in adults and its incidence increases with age. Diagnostic cytogenetics is an important prognostic indicator for predicting outcome of AML. We examined the karyotypic patterns of 480 patients with de novo AML seen at government hospitals throughout the country and evaluated the association of chromosome aberrations with the age of patient. Chromosome abnormalities were detected in 146 (30.4%) patients. The most common cytogenetic abnormality was balanced translocation t (8; 21), followed by trisomy 8 (as sole abnormality) and t (15; 17). The age of our Malaysian patients at diagnosis ranged from four months to 81 years, with a median age of 39 years. The normal karyotype was found mainly in patients aged 15-30 years. About 75% of patients with t (8; 21) were below 40 years of age, and the complex karyotype was found with the highest frequently (34.3%) in elderly patients (age above 60 years). More than half of the patients with complex karyotype were above 50 years of age. The deletion 5q was detected only in patients aged above 50 years. Different cytogenetic abnormalities in AML show different frequencies with increasing age. Probably different genetic mechanisms are involved in the pathogenesis of AML and these mechanisms might occur at different frequencies over lifetime.