Brain cancers include primary brain tumours, which start in the brain and almost never spread to other parts of the body, and secondary tumours (or metastases), which are caused by cancers that began in another part of the body.
There are more than 40 major types of brain tumours, which are grouped into two main types:
- benign - slow - growing and unlikely to spread. Common types are meningiomas, neuromas, pituitary tumours and craniopharyngiomas.
- malignant - cancerous and able to spread into other parts of the brain or spinal cord. Common types include astrocytomas, oligodendrogliomas, ependymomas, glioblastomas and mixed gliomas.
The risk of being diagnosed with a brain cancer by age 85 is 1 in 110 for men and 1 in 154 for women.
Brain cancer symptoms
Headaches are often the first symptom of a brain tumour. The headaches can be mild, severe, persistent, or come and go.
Other symptoms include:
- difficulty speaking or remembering words
- disturbed vision, hearing, smell or taste
- seizures: severe (eg. a convulsion) or mild (as in a fleeting disturbance of awareness, sensation or jerking muscles)
- weakness or paralysis in part of the body
- loss of balance
- general irritability, drowsiness or a change in personality
- nausea and vomiting.
Causes of brain cancer
The causes of brain tumours are not known but some risk factors include:
- some brain and spinal cord tumours are more common in people with certain inherited or genetic conditions
- people exposed to very high doses of radiation to the head.
Screening for brain cancer
There is no routine screening test for brain cancer.
Diagnosis for brain cancer
If a brain tumour is suspected, the doctor may check how different parts of the brain are functioning by checking the patient’s reflexes, muscle strength, ability to feel pin-pricks and to distinguish between hot and cold. An opthalmoscope is used to view the optic nerve, which may bulge if the pressure in the skull is raised, for example by a tumour.
Diagnosis is usually by MRI and CT scans.
Other tests that are sometimes used are:
- magnetic resonance spectroscopy
- PET scan
- single photon emission CT scan
- lumbar puncture (also known as spinal tap).
Treatment for brain cancer
MRI and CT scans and other tests, if used, determine the extent of the cancer (its stage).
Brain tumours are usually graded on a scale of I to IV, based on how quickly they are growing and their ability to invade nearby tissue: grades I and II are the slowest growing and are called low-grade tumours; grade IV is the fastest growing.
Types of treatment
Brain tumours may be treated with surgery, radiotherapy, chemotherapy or steroid therapy, or a combination of these treatments.
Some tumours can be removed completely by surgery (craniotomy). Post-operative radiotherapy improves local control and survival. For glioblastomas, temozolomide may be added during or after radiotherapy to further improve outcomes.
If a tumour cannot be removed, the aim of treatment is to slow growth and relieve symptoms by shrinking the tumour and any swelling around it. Treatment options include radiotherapy with or without temozolomide.
Your treatment will consist of a number of specialists depending on the type of treatment you have. These may include:
- neurologist – diagnosis and treats diseases of the brain and nervous system
- neurosurgeon – uses surgery to treat brain diseases and injuries
- cancer nurses
- medical oncologist – diagnoses and treats cancer using chemotherapy
- radiation oncologist – diagnoses and treats cancer with radiotherapy
- other health professionals such as dietician, social worker, speech and occupational therapists.
Prognosis for brain cancer
An individual's prognosis depends on the type and stage of cancer, as well as their age and general health at the time of diagnosis. For benign tumours that can be completely removed, cure is likely. For malignant tumours, outcomes depend on how slowly or quickly the tumour develops and response to treatment.
Across all brain cancers, the five year survival rate is 22%.
Preventing brain cancer
There are no proven measures to prevent brain cancer.