Leukaemias are a group of blood cancers that can occur in people of any age, from young children to the elderly.
Leukemia is a cancer of the blood and bone marrow. All leukaemias start in the bone marrow where the developing white cells undergo a malignant change. They multiply in an uncontrolled way crowding the bone marrow and interfering with the normal blood cells production.
Two types of white blood cells can be involved: lymphoid or myeloid and their cancers are named after them.
Some leukaemias appear suddenly and progress rapidly over days to weeks. These are called acute leukaemias. Others progress slowly over months to years, these are the chronic leukaemias. Each type of leukaemia needs different treatment.