40% of all cancers spread to the brain
A meningioma is a tumour of the meninges, the thin sheets of body tissue inside the skull which help to protect the brain.
These are called the meninges and they help to provide a protective lining for the brain and spinal cord. It can occur in any part of the brain or spinal cord, but the most common sites are at the surface of the brain, either over the top or at the skull base. They are usually benign (not cancerous).
Some meningiomas are ‘a-typical’. This means that they behave more aggressively than normally expected for meningiomas. They can grow into surrounding brain tissue and may come back after they have been removed.
About 1 in 4 primary brain tumours in adults (25%) is a meningioma. They are more common in older people and in women. They are most often found in the forebrain or hindbrain. They are usually benign (not cancerous).