Myeloproliferative Neoplasms

Myeloproliferative neoplasms (MPNs) are a group of blood cancers that cause excess blood cell production in the bone marrow and often in the peripheral blood, and are characterized by clonal genetic changes. MPNs include chronic myeloid leukemia (CML), polycythemia vera (PV), essential thrombocythemia (ET), primary myelofibrosis (PMF), chronic neutrophilic leukemia (CNL), and chronic eosinophilic leukemia (CEL). CML, which is discussed separately, is defined by the presence of the BCR-ABL1 fusion gene; the other MPN types are BCR-ABL1 negative. The majority of patients with PV, ET, and PMF have a mutation in the JAK2, CALR, or MPL gene, which carries implications for classification, diagnosis, and prognosis; however, other clonal markers may also be diagnostic for MPN.

Laboratory testing for the evaluation of MPN includes an initial workup of blood counts (CBC). Peripheral blood smear microscopy, bone marrow histology, cytogenetics, and genetic profiling complete the diagnostic testing. A diagnosis is made when results of these studies meet the specific diagnostic criteria for a particular MPN subtype. Distinguishing MPN types and grades is essential because treatments vary and long-term clinical outcomes differ significantly among the subtypes. 

Tabs Content
Content Review: 
October 2019

Last Update: December 2019