The term brain metastasis refer to cells (usually cancerous) which have moved from a different part of the body to the brain.
Brain metastases are the most common types of brain tumours, and are an important cause of disability and mortality (death) in cancer patients.
The most common types of cancer that spread to the brain, resulting in cerebral metastases, are lung, breast, bowel and kidney cancer, as well as melanoma. Lung and breast cancer account for most brain metastases, however in Australia melanoma is also a very common cause.
Cerebral or cerebellar (named after which part of the brain they affect) metastases usually occur in the brain tissue itself, but occasionally arise from the lining of the brain or the skull.
Brain metastases may cause a number of symptoms, including:
- nausea and vomiting
- seizures, also known as epileptic fits
Focal neurological symptoms are also seen in some patients with metastatic tumours, including:
- poor balance
- speech problems
Brain metastases may be treated with significant impact using a combination of surgery or stereotactic radiosurgery, radiotherapy, and frequently chemotherapy.
Most people with brain metastases are treated with medications to reduce swelling (oedema) around the tumour- the most commonly used medication is a corticosteroid called dexamethasone. Some patients are also treated with anticonvulsants to stop seizures. Dexamethasone has a number of side effects, and you should ask your neurosurgeon about these.
Neurosurgery (brain surgery) is an important part of the treatment of many patients with cerebral metastases, in order to obtain a diagnosis, reduce the amount of pressure on the rest of the brain, improve some of the symptoms, and possibly to extend survival.
Patients with tumours less than 3cm in size may be suitable for stereotactic radiosurgery. This is a non-invasive treatment which does not involve open surgery. In appropriately selected patients the results are equivalent to surgery, but it has the advantage of fewer risks, no need to be hospitalised for more than a few hours, and a much faster recovery time. Your neurosurgeon is best placed to discuss this option with you.