Leukaemia is the most common cancer of childhood, with about 400 new cases each year in the UK. It is a cancer of the tissues that produce blood cells. The body produces lymphocytes to protect it from infection, but in leukaemia these cells do not mature properly and become too numerous in the blood and bone marrow.
Leukaemias fall into two main types, acute or chronic. The most common type is acute lymphoblastic leukaemia. Other less common acute types may be grouped together as acute non-lymphoblastic leukaemia, including acute myeloid leukaemia.
Symptoms
Children with leukaemia usually become tired and lethargic due to anaemia, which is caused by lack of red blood cells. They may bruise easily or suffer infections because of low numbers of normal white blood cells. A child may complain of aches and pains in the limbs or have swollen glands, as if with a viral illness that does not go away.
Diagnosis
Leukaemia is usually diagnosed with a blood test that shows the presence of abnormal cells. A sample of bone marrow is then required to confirm the diagnosis.
Treatment
Chemotherapy, which kills the cancerous cells, is usually used to treat leukaemia. It can be given in various ways, either by mouth or intravenously by injection into a vein. Children are often given chemotherapy via a central line to avoid the need for repeated injections.
The side effects are usually hair loss, nausea and vomiting. When chemotherapy fails, doctors can carry out a bone marrow or stem cell transplant from a healthy person, usually a relative with the best possible cell match. The outlook for children with leukaemia is much better than it used to be - seven in ten are now cured, compared with only three in ten in 1966.