Leukaemia is a broad term for certain types of blood cancer. It occurs when abnormal bloodforming cells in the bone marrow grow in an uncontrolled way. Leukaemia starts in the bone marrow – usually in the cells that would normally develop into white blood cells. Some leukaemias start in other types of blood-forming cells, such as the cells that develop into red blood cells and platelets.
Leukaemia causes the body to produce too many of the type of blood cell it affects. Because the leukaemia cells don’t develop into normal mature blood cells, they don’t function in the way that normal blood cells do – for example, to fight infections. When the leukaemia cells build up in the bone marrow and blood, there is less room for healthy blood cells. This can cause anaemia, infection and bleeding easily. The leukaemia cells may spread to other parts of the body, including the lymph nodes, liver, spleen, central nervous system (brain and spinal cord) and testicles.
Leukaemia is one of the 10 most common cancers in both men and women in Australia. It is the most common cancer in children and teenagers, making up around one-third of cancers in young people. Most of these cases are acute forms of leukaemia.