chronic myeloproliferative disorder

Introduction

Clonal hematopoietic stem cell disorders characterised by proliferation in the bone marrow of one or more myeloid lineage cell; associated with relatively normal maturation and increased numbers in peripheral blood. Differs from the ineffective hematopoiesis seen in myelodysplastic syndromes.

Classification

WHO

• chronic myelogenous leukemia
• chronic neutrophilic leukemia
• chronic eosinophilic leukemia and hypereosinophilic syndrome
• polycythemia vera
• chronic idiopathic myelofibrosis (with extramedullary hematopoiesis)
• essential thrombocythemia
• chronic myeloproliferative disease, unclassified

Etiology

• no specific genetic abnormalities identified
• activation of tyrosine kinase signal transduction pathways frequently implicated

Epidemiology

• primarily disease of adults, peak 5th - 7th decades
• 6-9/100,000 annually

Genetics

• chromosomal aberration involving ETV6 is a cause of chronic myeloproliferative disorder with eosinophilia

Clinical manifestations

• insidious onset
• splenomegaly, hepatomegaly common
  • sequestration of excess cells
  • extramedullary hematopoiesis
  • leukemic infiltration

Disease progression:

• potential to undergo clonal evolution
• bone marrow failure
  • myelofibrosis
  • ineffective hematopoiesis
  • transformation to acute blast phase

Laboratory

• complete blood count
• bone marrow biopsy
• 10-19% blasts in blood or bone marrow may signify disease acceleration
• 20% or more blasts suffieient for diagnosis of blast phase

More general terms

• myeloproliferative disorder
• chronic hematologic disease (chronic blood disorder)

More specific terms

• chronic myeloid leukemia (CML, granulocytic leukemia)
• chronic myelomonocytic leukemia (CMML)
• polycythemia rubra vera (PRV, PV, erythremia)

Database

• OMIM: https://mirror.omim.org/entry/131440