Comparison Between WHO-classification And FAB Subtypes In Adult Acute Leukemia Patients

[BACKGROUND]: During the nearly 3 decades that the FAB system was used for classifying AL, the FAB classification recognizes the morphologic heterogeneity of AL, it does not always reflect the genetic or clinical diversity of the disease.Cytogenetic analysis is the most important diagnostic tool for determining prognosis in AL. it has been clearly shown that the cytogenetic features often correlate closely with specific morphologic, immunophenotypic, and clinical parameters.In the majority of patients with acute myeloid leukemia (AML), acquired clonal chromosome aberrations can be observed. Numerous recurrent karyotype abnormalities have been discovered in AML. AML is a very heterogeneous disease with over 160 structural chromosome abnormalities observed recurrently to date. These findings on the chromosomal level have paved the way for molecular studies that have identified genes involved in the process of leukemogenesis. The identification of specific chromosomal abnormalities and their correlation with cytomorphologic features, immunophenotype, and clinical outcome have led to a new understanding of AML as a heterogeneous group of distinct biologic entities. The importance of cytogenetic findings in AML for classification and for the understanding of pathogenetic mechanisms is increasingly appreciated in the clinical context.Karyotypic investigations are now routinely performed for diagnostic and prognostic purposes in acute lymphoid leukemia (ALL), with the chromosomal abnormalities/cytogenetic patterns playing a major role for...