Myeloproliferative neoplasm

The myeloproliferative neoplasms (MPNs) or disorders are a group of chronic disorders characterized by increased proliferation of neoplastic haematopoietic stem cells of one or more of the myeloid cell lineages, the erythroid, granulocytic, and megakaryocytic lineages. Unlike in myelodysplastic syndromes, the stem cells are nondysplastic. The classic MPNs are:

• Chronic myeloid leukaemia
• Polycythaemia vera
• Essential thrombocythaemia
• Primary myelofibrosis

The main difference between CML and the other classic MPNs is that the BCR-ABL1 (Philadelphia chromosome) translocation only occurs in CML.

All MPNs can progress into acute myeloid leukaemia or secondary myelofibrosis leading to bone marrow failure.