Last edited 05/2019 and last reviewed 05/2019
- malignant neoplasms of the haemopoietic stem cells
- primary neoplasms of the bone marrow
The malignant cells gradually replace the normal bone marrow and may spill over into the peripheral circulation.
Leukaemias may be divided into:
- acute leukaemias:
- show rapid proliferation of relatively undifferentiated malignant cells
- are characterised by the development of bone marrow failure with consequent anaemia, neutropenia, and thrombocytopenia
- are the most common leukaemias among children
- chronic leukaemias:
- have a relatively prolonged natural history
- are characterised by better differentiated malignant cells
- compromise marrow function at a late stage
- have features of the large load of malignant cells e.g. hepatosplenomegaly
- are rare in children
Leukaemia is the most common childhood malignant disease - with an incidence of 3.5 per 100,000 per year in children under the age of 15 years. But as a whole, it is more common in the elderly - 60% occuring in patients over 50 years of age.