Acute myeloid leukemia (AML) is a clinically complex and very heterogeneous disease at the molecular level. Conventional cytogenetic analysis and FISH (fluorescence in situ hybridization) tests provide important information about the biological and clinical background of the disease and enable the classification of AML patients into three risk groups. However, up to half of patients have normal cytogenetics. Determining prognosis and treatment strategies in this group of patients is challenging. The development of molecular genetic methods, including next generation sequencing in the last decade, has led to the discovery of a number of recurrent mutations that have contributed to increasing the accuracy of prognosis of those patients with cytogenetically normal AML. Besides the prognostic value of these mutations, they may also be used to monitor minimal residual disease during and after treatment of AML and additionally constitute potential targets for the development of new therapeutic agents. The importance of molecular genetic testing of all patients with AML is highlighted by the WHO classification of 2008 in which subgroups of AML are purely defined by molecular genetics markers.
In this article, we provide an overview of the most significant mutations in patients with cytogenetically normal AML. We describe their significance for prognosis, their importance in monitoring minimal residual disease, and their potential for the development of new targeted therapies. Further, we briefly draw attention to the significance of gene mutation accumulation in clonal disease development and how it affects the time of AML relapse.