Classification of myeloproliferative neoplasms and chronic myeloproliferative disorders

Myeloproliferative neoplasms (MPN, chronic myeloproliferative disorders according to the former nomenclature) comprise chronic myeloid leukemia (CML), BCR-ABL positive CML, polycythemia vera (PV), primary myelofibrosis (PMF), essential thrombocythemia (ET), chronic eosinophilic leukemia (CEL) and chronic neutrophilic leukemia (CNL). The MPNs have a biphasic course in common with initial overproduction of one or more blood cell lineages, followed by hematopoietic insufficiency because of a blast crisis and/or bone marrow fibrosis. Classification and prognosis require a combined approach of morphological investigations, frequently including bone marrow histology and molecular pathological analysis with detection of characteristic driver mutations as well as the course of additional modulating genetic aberrations.