Myelodysplastic syndromes (MDSs) are characterized by a stem cell clonal disorder and ineffective hematopoiesis which causes dysplasia in one or more bone marrow hematopoietic cell lineages, peripheral cytopenia and genetic instability with enhanced risk to transform into acute myeloid leukemia (AML). This heterogeneous group of hematopoietic diseases can develop as primary diseases, which posses a variable and not completely defined etiology, or as secondary to chemotherapy or radiotherapy for other neoplasias. The evolution of diagnostic tests has improved comprehension of the process involved in the genesis and evolution of MDSs, making the development of earlier and more specific tests for diagnosis and follow ups possible. In 2008, the World Health Organization (WHO) redefined the criteria for the classification of MDSs, dividing them into seven subgroups. This classification included new immunophenotypic, genetic, cytomorphologic and molecular features, which are essential for the diagnosis of MDSs and for a better comprehension of the disease. Despite technological advances, some details, such as the molecular basis of the transformation of MDS to AML, are still not completely understood, which makes further studies in this field necessary. Hence, the objective of this review is to make a compilation of recent molecular and laboratory aspects of MDS.
Myelodysplasic syndrome; WHO Classification 2008; immunophenotyping
