Leukaemia is a collective term for cancer-like blood diseases in the blood-building bone marrow, where the white blood cell count is highly elevated. Symptoms of leukaemia are easy bruising and chronic wounds, as well as anaemia and shortness of breath. A deficiency of white blood cells makes people more prone to infection.

Leukaemia is usually divided into two major sub-types: myeloid and lymphocytic leukaemia. These can be further sub-divided into acute and chronic leukaemia. Acute leukaemia occurs from immature cells and develops rapidly, often within a few weeks. Chronic leukaemia has a slow disease progression and can progress for many years without the need for treatment.

Acute lymphatic leukaemia is most common in children while chronic lymphatic leukaemia and myeloid leukaemia are most common in adults.