There are 45 new cases per 100.000 population each year in the UK. However, the majority of tumours found in the brain are not primarily brain tumours but have spread to the brain from other parts of the body.
Some tumours may be induced by radiation. It is known that children who were treated by radiation to the scalp to eradicate fungal infections had an increased incidence of brain tumours. Children who received irradiation of the brain for past of their treatment for leukaemia also have an increased risk (1:100 to 1:200) of developing a brain tumour in the future.
Other possible causes include infection with viruses, electromagnetic radiation, and chemical agents. In some cases a tumour may appear in a similar area to a previous head injury.
Brain tumours can be associated with inherited disorders of nerve cell development. This overgrowth of nerves is associated with overgrowth of the overlying skin in some cases known as neurofibromatosis.
There are no associations with deficiencies or excess of dietary components although it has been suggested that anti-oxidants such as Vitamin E may be protective.
Symptoms and signs
The commonest symptom is headache which in many cases is worst on arising in the morning. The headache can be more severe on coughing or straining. Problems with vision or difficulty with speech may also occur.
An epileptic attack may be the first presenting sign especially in adults. Other symptoms include changes in personality such as loss of interest in normal activities, loss of concentration and irritability that can be mistaken as depression.
The development of weakness of an arm, leg or one side of the face may be the first sign of pressure in the brain caused by a tumour. Others may present with unexplained vomiting in the absence of abdominal pain or indigestion.
Surgery is the preferred method of treatment but not be possible due to its position in the brain. However there are new techniques using localised radiotherapy to access these tumours.
If it is not possible to remove the entire tumour then radiotherapy or chemotherapy can also be used.