Clinical outcome of de novo acute myeloid leukaemia patients with normal cytogenetics is affected by molecular genetic alterations:: a concise review

Normal cytogenetics are detected pretreatment in approximately 45% of patients with de novo acute myeloid leukaemia (AML); thus this constitutes the single largest cytogenetic group of AML. Recently, molecular genetic alterations with prognostic significance have been reported in these patients. They include internal tandem duplication of the FLT3 gene, partial tandem duplication of the MLL gene, mutations of the CEBPA and NPM1 genes and aberrant expression of the BAALC, ERG and MN1 genes. Additionally, gene-expression profiling has been applied to identify prognostically relevant subgroups. Substantial progress has been made in the understanding of molecular pathways deregulated in leukaemogenesis and how these defects can be targeted by novel therapeutic compounds. Here we critically review the molecular heterogeneity among AML patients with normal cytogenetics and discuss how these data may translate into a prognostic, molecular-based treatment stratification that may improve the currently unsatisfactory outcome of these patients.