A meningioma is a type of tumor. It grows in the meninges. These are thin layers of tissue that cover and protect the brain and spinal cord. Technically, a meningioma is not a brain tumor. This is because it does not start in brain tissue. But it's often referred to as a brain tumor.

Most of these tumors are grade 1 (benign), which means they grow slowly. Some are grade 2 or grade 3, which grow faster and need more treatment. A grade 1 meningioma can still cause neurological problems because of its location. As these tumors grow, they can compress the brain and spinal cord. This leads to serious symptoms.

Meningiomas are the most common type of brain tumors in adults and occur more often than cancerous brain tumors. They're more common in biological females. They typically develop between ages 40 and 60. Children rarely get meningiomas.

The underlying cause of meningiomas is not clear. Hormonal fluctuations may encourage the growth of these tumors. But more research is needed to confirm this.

Researchers have found a chromosome defect in many meningiomas. This suggests that the tumors may be caused by genetic-related factors. The specific chromosome involved functions to suppress tumor growth.

Females are much more likely to get meningiomas than males. This has led experts to suspect that certain hormones might play a role in the development of these tumors. Other people at higher risk include those who have had radiation treatment to the head and people with neurofibromatosis. This is an inherited nervous system disorder.

These tumors usually grow slowly. You may not have any symptoms until the tumor has become large. The tumor can cause different symptoms, depending on where it's growing. These are possible symptoms:

• Vision or hearing loss, or ringing in the ears
• Seizures
• Trouble thinking clearly
• Trouble walking
• Loss of smell
• Weakness in an arm or leg
• Headache
• Nausea
• Change in personality or behavior

A meningioma is often found because of symptoms a person is having. To diagnose a meningioma, these tests may be done:

• Neurological exam. Your doctor will ask about your symptoms. They may do a neurological exam to look for changes in motor and sensory function, vision, coordination, balance, mental status, and in mood or behavior.
• Imaging. Your doctor may diagnose a meningioma using an MRI or CT scan. This is to get a picture of the brain and nearby structures.
• Biopsy. In addition, your doctor may want to remove a small sample of the tumor to examine it at the lab under a microscope before making the diagnosis.

Not all meningiomas need to be treated right away. Close observation may be the best choice for those with few symptoms and little to no brain swelling in the nearby areas. Or for those who experience a significant risk with treatment. Some people may find that a second opinion about treatment helps in their decision-making.

Your doctor will likely want to remove it with surgery if your meningioma is causing symptoms or is growing. In some cases, though, trying to remove the tumor may be too risky. For example, the tumor may be too close to vital brain structures or blood vessels.

If you do have surgery, the surgeon will try to take out as much of the tumor as possible. The surgeon may use MRI scans of your brain to help guide the surgery. The surgeon may also use a special microscope during the surgery to get a better view of the tumor and the surrounding parts of your brain.

If the surgeon can't remove the tumor—or can only remove part of it—you may need radiation therapy. Depending on the areas of the brain or spinal cord that are involved, radiation therapy may help shrink any remaining tumor and can also help prevent it from spreading to the tissues around it. Even if the tumor is completely removed during surgery, some doctors may still recommend radiation therapy to help prevent another meningioma from developing in the future. Meningiomas have a tendency to grow back after surgery. Radiation treatment is sometimes given with more precision by using a gamma knife or cyberknife.

Your doctor may also recommend medicine to treat the tumor or some of the symptoms related to the tumor. Clinical trials are underway that are studying several different medicines to see if they are effective in treating meningiomas. You may need to take part in a study to be able to use these medicines.

You may also be prescribed other types of medicines to treat symptoms caused by the meningioma, such as seizures, excessive vomiting, weakness, and vision disturbances.

In many people, a meningioma doesn't cause any symptoms and grows quite slowly. For this reason, experts might recommend watchful waiting. This means you will report any new symptoms to your doctor. They will also order scans on a regular basis to track even minor changes in the tumor. This may be a reasonable option for managing small tumors that aren't causing symptoms, especially in older adults who may not be able to have surgery or radiation therapy because of other medical conditions.

• A meningioma is a type of tumor. It grows in the meninges. These are thin layers of tissue that cover the brain and spinal cord. These tumors are usually not cancerous (benign). But they can still grow and press on the brain. This can lead to serious symptoms.
• Symptoms depend on where the tumor is. They can include headache, nausea, vision or hearing loss, seizures, trouble thinking, loss of coordination, or weakness in an arm or leg.
• A meningioma may not need to be treated right away. If treatment is needed, surgery is usually the first option if it can be done. Radiation therapy can also be used, either alone or along with surgery.

Tips to help you get the most from a visit to your doctor:

• Know the reason for your visit and what you want to happen.
• Before your visit, write down questions you want answered.
• Bring someone with you to help you ask questions and remember what your doctor tells you.
• At the visit, write down the name of a new diagnosis and any new medicines, treatments, or tests. Also write down any new instructions your doctor gives you.
• Know why a new medicine or treatment is prescribed and how it will help you. Also know what the side effects are and when they should be reported.
• Ask if your condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if you do not take the medicine or have the test or procedure.
• If you have a follow-up appointment, write down the date, time, and purpose for that visit.
• Know how you can contact your doctor if you have questions, including after office hours and on weekends and holidays.