leukaemia

Syringes are used to harvest bone marrow from the pelvis of a donor prior to transplantation into a patient with leukaemia. Bone marrow is rich in blood-forming and immune system cells. Donated bone marrow can be used to save the lives of patients whose own marrow cells have been destroyed by the chemotherapy and radiotherapy needed to eradicate their cancers.

Any one of a group of cancers of the blood cells, with widespread involvement of the bone marrow and other blood-forming tissue. The central feature of leukaemia is runaway production of white blood cells that are immature or in some way abnormal. These rogue cells, which lack the defensive capacity of healthy white cells, overwhelm the normal ones, leaving the victim vulnerable to infection. Treatment is with radiotherapy and cytotoxic drugs to suppress replication of abnormal cells, or by bone-marrow transplantation.

Abnormal functioning of the bone marrow also suppresses production of red blood cells and blood platelets, resulting in anaemia and a failure of the blood to clot.

Leukaemias are classified into acute or chronic, depending on their known rates of progression. They are also grouped according to the type of white cell involved.

The US has about 198,000 leukemia patients, according to the Leukemia Society of America. It is estimated that there will have been over 34,000 new cases in 2005, with more than half of the victims being people 60 or older. It is estimated that about 22,570 Americans will have died of the disease in 2005.