Myeloproliferative neoplasms (MPNs) refer to a group of neoplastic disorders characterized by clonal proliferation of one or more relatively mature myeloid cell lineages. In 1951, William Dameshek introduced the term myeloproliferative disorders (MPDs) to describe conditions such as chronic myelogenous leukemia (CML), polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). In 2008, the World Health Organization (WHO) reclassified MPDs as myeloproliferative neoplasms (MPNs), and these four diseases are now collectively referred to as classic MPNs. MPNs are characterized by a long disease course, and as the disease progresses, some cases may transform into other diseases or undergo subtype transitions.
PV, ET, and PMF are collectively referred to as BCR::ABL1-negative myeloproliferative neoplasms (BCR::ABL1-negative MPNs).
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