A meningioma is a tumor that arises from the membranes that surround the brain and spinal cord, which are known as the meninges. Most meningiomas are noncancerous (benign), though on occasion, they may be cancerous (malignant). Some meningiomas are classified as atypical — which means they’re neither benign nor malignant but, rather, something in between. Meningiomas occur most commonly in older women. But a meningioma can occur in males and at any age, including childhood. A meningioma doesn’t always require immediate treatment. A meningioma that causes no significant signs and symptoms may be monitored over time.

What are the symptoms?

Signs and symptoms of a meningioma typically begin gradually and may be very subtle at first. Depending on where in the brain or spine the tumor is located, the signs and symptoms may include:

  • Changes in vision, such as seeing double or blurriness
  • Headaches that worsen with time
  • Hearing loss
  • Memory loss
  • Loss of smell
  • Seizures
  • Weakness in the arms or legs

Many of the signs and symptoms of a meningioma develop slowly, but sometimes a meningioma requires emergency care. Patients should seek emergency care if they have sudden onsets of seizures or sudden changes in vision or memory.

How is it caused?

The causes of a meningioma are not clear. Doctors believe that something causes certain cells in the meninges to multiply out of control leading to a meningioma tumor. It is still unknown whether meningiomas form because of inherited genes, environmental causes, hormones or a combination of these factors.

How is it diagnosed?

A meningioma may be detected on an imaging test, such as computerized tomography, which takes X-rays in the shape of cross-sectional images (like slices) of the brain and head. These images are combined together by a computer to create a full picture of the brain. A meningioma may also be diagnosed with magnetic resonance imaging (MRI). With this imaging study, a magnetic field and radio waves are used to create cross-sectional images of the structures within the brain. MRI scans provide a more detailed picture of the brain and meningiomas.

What are the treatment options?

The treatment for a meningioma depends on the size of the meningioma, where it’s situated and how aggressive it’s believed to be. The doctor will also take into consideration a patient’s overall health and goals for treatment.

Doctors don’t always recommend immediate treatment for a patient with a meningioma. A small, slow-growing meningioma without symptoms may not require treatment. If the doctor does not recommend treatment for a meningioma, a patient will likely have brain scans periodically to evaluate the meningioma for signs of growth. If the doctor determines the meningioma is growing and needs to be treated, there are several treatment options.

If a meningioma is causing symptoms and showing signs of growth, a doctor may recommend surgery. Surgeons work to remove the meningioma completely. Since a meningioma may form near many delicate structures in the brain or spinal cord, it’s not always possible to remove the entire tumor. In those cases, surgeons remove as much of it as possible.

Following the surgery, if no visible tumor remains, no further treatment may be necessary. If the tumor is benign and only a small piece remains, then the doctor may recommend periodic follow-up scans. In some cases, small leftover tumors may be treated with a form of radiation treatment known as stereotactic radiosurgery. If the tumor is atypical or malignant, then a patient may need radiation therapy. The risks of surgery include infection and bleeding. The specific risks of a patient’s surgery will depend on the location of the meningioma. Patients should ask their surgeons directly about the details of their surgery.

If a meningioma can’t be completely removed, the doctor may recommend radiation therapy after the surgery. The goal of radiation therapy is to destroy any remaining meningioma cells and reduce the chance of recurrence. Radiation therapy uses a large machine to aim high-powered energy beams at the tumor cells.

Advances in radiation therapy increase the dose of radiation to the meningioma while reducing radiation to healthy tissue. These include fractionated stereotactic radiotherapy (SRT) and intensity-modulated radiation therapy (IMRT).

Radiosurgery is a type of radiation treatment that aims several beams of powerful radiation at a precise point. This treatment doesn’t involve scalpels or incisions. Radiosurgery is usually done in an outpatient setting in a few hours. Radiosurgery may be an option for people with meningiomas that can’t be removed with conventional surgery or for meningiomas that recur despite treatment.
When meningiomas recur or don’t respond to surgery and radiation, doctors may try different treatments. Most chemotherapy treatments have not proved effective to date, but some medications, such as hydroxyurea (Droxia®, Hydrea®), are sometimes used. Other drugs are being tested as well, such as those that prevent the release of growth hormones. Some medications that stop the tumor’s ability to form blood vessels (angiogenesis inhibitors) are seen as promising, but the data is preliminary. More study is still needed in this area.