Overview
A brain tumour is an abnormal growth of cells in or around the brain. Tumours can be primary (starting in the brain) or secondary (spread from cancer elsewhere). Non-cancerous tumours often grow slowly; cancerous tumours vary in grade and growth rate. Either can cause serious problems depending on location and pressure on the brain.
How common is it?
More than 12,000 people in the UK are diagnosed with a primary brain tumour each year. Many other people develop secondary brain tumours from cancer elsewhere in the body.
Causes and risk factors
Most brain tumours have no identifiable cause. In secondary (metastatic) tumours, cancer cells from lung, breast, kidney, or skin melanoma travel through the bloodstream and form deposits in the brain.
Common risk factors
- Previous radiation to the head (strongest known risk factor)
- Rare inherited conditions such as neurofibromatosis or Li-Fraumeni syndrome
- Age: risk increases with age for most types
- Immunosuppression
- Secondary tumours from breast, lung, kidney, melanoma
Symptoms
- Persistent or progressive headaches, often worse in the morning
- Seizures with no prior history
- Gradual weakness or numbness on one side of the body
- Personality or mood changes
- Memory problems or confusion
- Vision or speech difficulties
- Nausea and vomiting not explained by other causes
When to see a doctor
Seek emergency help for a first seizure, a prolonged seizure, repeated seizures without recovery, or sudden weakness, speech difficulty or reduced consciousness. Do not assume that these symptoms can wait for a routine brain-tumour appointment. Arrange prompt medical assessment for new or worsening headaches or progressive neurological changes.
Diagnosis
MRI scan with contrast is the primary diagnostic tool. Biopsy of tumour tissue obtained during or before surgery gives the definitive diagnosis. Blood tests and CT of the chest, abdomen, and pelvis look for a primary cancer site if metastasis is suspected.
Treatments
Surgery
Surgical removal (resection) is the primary treatment where possible. Maximising how much tumour is safely removed improves outcomes while preserving brain function.
Radiotherapy
High-energy radiation targeted at tumour cells. Used after surgery for malignant tumours or alone for tumours that cannot be surgically removed safely.
Chemotherapy and targeted therapy
Chemotherapy may be used depending on tumour type and grade. Molecular test results can help identify selected targeted treatment options. New treatments may be available through clinical trials, but are not suitable or routinely available for everyone.
Self-care and lifestyle
- Rehabilitation therapy addresses specific deficits in speech, movement, or cognition after surgery
- Prescribed corticosteroids may reduce brain swelling. Ask about glucose monitoring if you have diabetes, and do not change or stop steroids without the treating team's advice
- Anti-epileptic medication is needed for anyone who has had seizures
- Palliative care improves quality of life at all stages of treatment
Prevention
There are no proven lifestyle modifications that reliably prevent brain tumours. Regular monitoring is advised for people with known inherited risk conditions.
Sources for targeted updates
Updated: 24 October 2026. Targeted corrections to overview, frequency, treatment, self-care, key facts. This update covers the named sections; a full review of the remaining guide is pending.