Meningiomas are tumors arising from the membranes (meninges) that cover the brain and spinal cord. Most are benign and slow-growing. Treatment options include observation, surgery and radiosurgery.
What is a meningioma?
A meningioma is a tumor that develops from cells in the arachnoid layer of the membranes covering the brain and spinal cord. It is one of the most common tumors of the brain and spinal cord. It is more frequent in women than in men and usually appears in middle and older age.
The great majority of meningiomas are benign (World Health Organization grade 1) and grow slowly. Less common grade 2 and grade 3 meningiomas tend to grow faster and recur.
Because the tumor grows by pressing on the brain from outside rather than invading it, it may cause no symptoms for a long time. Some meningiomas are therefore discovered incidentally on an MRI performed for another reason.
Symptoms
Symptoms depend on the location and size of the tumor:
- Headache
- Seizures
- Weakness or numbness of an arm or leg
- Loss of vision or narrowing of the visual field
- Loss of sense of smell
- Hearing loss and imbalance
- Personality change and forgetfulness
Diagnosis
Contrast-enhanced brain MRI is the key investigation. CT may be used to assess the relationship with bone, and angiography when needed to show the relationship with blood vessels. The definitive diagnosis and grade are established by pathological examination of the surgically removed tissue.
Treatment Approach
- Observation: Small meningiomas that cause no symptoms and do not grow can be monitored with regular MRI.
- Surgery: The main treatment for meningiomas that cause symptoms, are growing or are large. The aim is to remove the tumor together with its dural attachment and, if necessary, the involved bone, without damaging surrounding structures.
- Radiosurgery: May be delivered with Gamma Knife or CyberKnife for small and medium-sized meningiomas, particularly in high-risk locations such as the skull base, or for residual or recurrent tumor after surgery. The aim is to stop tumor growth.
- Radiotherapy: May be added after surgery for grade 2 and grade 3 meningiomas.