Chronic myelomonocytic leukemia (CMML) is a hematopoietic stem cells disorder, it carries myelodysplastic and myeloproliferative features. CMML occurs rarely, especially in the elderly, and often transforms into acute myelogenous leukemia.
Recently, in a large proportion of patients sophisticated molecular-biology technologies can determine mutations in epigenetic regulatory genes (e. g. TET2, ASXL1, ...) that modify chromatin condensation and also gene expression.
These facts support the inclusion of hypomethylating agents (HMA) in the standard treatment of CMML and opened the gates for the use of other new molecules. The aim of this paper is to describe concrete examples of current diagnostics and treatment of CMML and demonstrate the complexity of the new approaches.