Myeloproliferative Neoplasms

The answer first

Myeloproliferative neoplasms (MPNs) are clonal stem cell disorders characterised by overproduction of one or more myeloid lineages: polycythaemia vera (PV) (erythrocytosis), essential thrombocythaemia (ET) (thrombocytosis), and primary myelofibrosis (PMF) (fibrosis, extramedullary haematopoiesis, cytopenias). All three share the JAK-STAT pathway activation from JAK2, CALR, or MPL mutations; JAK2 V617F is present in 95 per cent of PV, 50-60 per cent of ET, and 50-60 per cent of PMF. The FRACP candidate must defend the diagnostic criteria (WHO 2016/2022), the thrombotic risk stratification (IPSET-thrombosis for ET; IPSS for PMF), the indications for ruxolitinib (symptomatic MF, symptomatic splenomegaly, high-risk PV), and the unique management of pregnancy in MPN (interferon alpha first-line). ^{[1] [6]}

The answer-first synthesis is: confirm the clonal nature of the myeloproliferation (JAK2/CALR/MPL mutation, EPO level, marrow biopsy); classify by disease entity (PV, ET, PMF); stratify thrombotic and fibrotic risk; manage by disease (phlebotomy plus low-dose aspirin for PV; cytoreduction with hydroxycarbamide or anagrelide for high-risk ET; ruxolitinib or fedratinib for symptomatic MF; allogeneic stem cell transplant for transplant-eligible high-risk MF). ^{[2] [5]}

References11ShowHide

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