Chronic myeloid leukaemia

Keywords: Chronic granulocytic leukaemia, CML

Complications

Appropriate Tests

Chronic myeloid leukaemia, BCR-ABL1 positive (CML, previously chronic granulocytic leukaemia) is a Myeloproliferative neoplasms in which the abnormal pluripotent bone marrow stem cell gives rise to predominantly excessive granulocyte production. It is consistently associated with the BCR-ABL1 fusion gene located in the Philadelphia chromosome

Full blood count and Blood film – neutrophilia with immature myeloid precursors, typically myelocytes; basophilia +/- eosinophilia, thrombocytosis with giant platelets.

Peripheral blood BCR-ABL PCR can be requested.

Full assessment requires a peripheral blood sample for BCR-ABL PCR, and a Bone marrow biopsy aspirate and trephine for accurate blast and basophil percentage quantification, determination of any extra cytogenetic abnormalities aside from the Philadelphia chromosome.

Complications:

 
  • Splenomegaly

Not always, especially if early stages.

  • Hyperuricaemia

Urate.

  • Acute leukaemia

The natural history of CML comprises 3 stages:

  • Chronic phase – typical Full blood count abnormalities as described above;
  • Accelerated phase – thrombocytopenia unrelated to therapy, additional cytogenetic abnormalities, increasing basophil counts or blasts in blood or bone marrow, or uncontrolled leucocytosis or thrombocytosis despite therapy;
  • Blast crisis – >20% blasts in peripheral blood or bone marrow or where there is extramedullary blast proliferation.