Meningioma

Summary

• A meningioma is a tumour in the membranes surrounding the brain and spinal cord.
• Meningiomas are mostly benign, but can occasionally be malignant.
• Symptoms depend on the size and location of the tumour.
• Meningioma is usually successfully treated with surgery and radiation.
• It is more common in women than in men.

Alternative names

Brain tumour

What is meningioma?

Meningioma is a tumour in the meninges - membranes surrounding the brain and spinal cord. They are only rarely malignant (cancerous - invasive of surrounding tissue and spreading to other organs); however, benign tumours can also cause serious damage.

Meningiomas are more common in women than in men. They are slow growing, taking years to develop, and most appear in people over the age of 40. Childhood meningiomas are rare.

What causes meningioma?

The development of tumours may be due to genetic or environmental factors that disrupt the orderly growth of cells, causing them to divide uncontrollably. While the reasons for this are unclear, risk factors include:

• Radiation therapy to the head
• Female hormones
• The rare genetic disorder neurofibromatosis Type 2

What are the symptoms of meningioma?

Because meningiomas are generally very slow-growing, symptoms may develop gradually. Many smaller tumours produce no symptoms.

However, larger tumours cause problems, which vary according to the tumour's size and position. Although not malignant, benign tumours can press on the brain and spinal cord and cause blockages. Most symptoms are the result of increased pressure in the brain, due to swelling around the tumour or to a build-up of cerebrospinal fluid.

Symptoms may include:

• Vomiting
• Seizures
• Changes in mood, behaviour and personality
• Paralysis on one side of the body
• Speech problems
• Coordination problems
• Memory loss
• Headaches
• Incontinence
• Changes in vision
• Hearing loss
• Weakness in limbs

How is a diagnosis made?

A doctor will ask about medical history and symptoms. A neurological examination will test if there are any abnormalities in nerve function. If so, a brain scan may be required to confirm the presence and location of a tumour, as well as any cancerous spread. Imaging techniques used include:

• CT (computerised tomography) scanning
• MRI (magnetic resonance imaging) scanning
• Angiography (also called an arteriography), which involves the injection of dye into the blood vessels

Usually, a scan is sufficient. Sometimes, however, a sample may be taken from the tumour for microscopic examination.

How is it treated?

Treatment depends on various factors, including the tumour's size and position, whether it is malignant, and the patient's general health.

• Any raised pressure inside the skull must be lowered before other treatment. Steroids may reduce swelling. If there is build-up of cerebrospinal fluid, a tube (shunt) is inserted to drain it.
• Generally meningiomas are removed by surgery. However, it is not always possible to remove a tumour completely, because it may be inaccessible, or lie too close to vital parts of the brain, spinal cord or eyes. In such cases, the tumour may recur. If a malignant tumour has invaded nearby bone, complete removal is almost impossible.
• Radiation therapy uses high-energy radiation beams to destroy cancer cells. This is used if the tumour is malignant, cannot be surgically removed, or after incomplete removal of a benign tumour, to reduce the chance of recurrence. Sometimes a particularly accurate technique known as radiosurgery is used, mostly for smaller tumours.
• Chemotherapy does not work on meningiomas, although research into this continues.

A small, slow-growing meningioma that isn't causing problems may not require treatment. In this case it is advisable to monitor the tumour with periodic brain scans.

What is the prognosis?

Meningiomas are mostly successfully and permanently removed. With complete removal, 80% of patients live for more than 10 years.Because meningiomas grow so slowly, they may be controlled for a long time without surgery, and in some cases may not need to be removed at all.

Malignant meningiomas are more likely to come back after surgery, and the life expectancy of such patients is shorter.

Complications

A meningioma may recur, especially if it was not initially completely removed.

Surgery may result in complications, including infection, bleeding, blood clots and cardiac trouble. There are particular risks involved with tumours in specific locations - such as near the optic nerve, with the risk of vision loss.

Healthy cells may be incidentally harmed by radiation therapy, causing problems such as memory loss, stroke, vision loss, and elevated risk of further tumours.

Being diagnosed with meningioma may be emotionally difficult. Patients may benefit from counselling, education, and support groups.

When to call your doctor

Call your doctor is you have any of the symptoms of a brain tumour. These will probably worsen gradually over time. Immediately call your doctor or emergency services if you experience abrupt changes in vision or memory or sudden seizures.

How can it be prevented?

There are no prevention prrocedures for meningioma at present.