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Chronic myelomonocytic leukemia

Disease definition

A rare myelodysplastic/myeloproliferative neoplasm characterized by a spectrum of clinical, hematological, and morphological features, ranging from predominantly myelodysplastic to mainly myeloproliferative in nature. Infiltration of the liver, spleen, lymph nodes, and other organs is common. Persistent peripheral blood monocytosis with monocytes accounting for more than 10% of leukocytes is the hallmark of the condition. Blasts constitute less than 20% of the cells in the peripheral blood and bone marrow. Other abnormalities are variable. Patients may present with constitutional symptoms, signs and symptoms of hematopoietic insufficiency, and hepatosplenomegaly. The disease is associated with a risk of transformation to acute myeloid leukemia.


Classification level: Disorder
  • Synonym(s):
    • CMML
  • Prevalence: -
  • Inheritance: Not applicable 
  • Age of onset: Adult
  • ICD-10: C93.1
  • ICD-11: 2A40
  • OMIM: -
  • UMLS: C0023480
  • MeSH: D015477
  • GARD: 8225
  • MedDRA: 10009018
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