Meningiomas

Meningiomas are tumors that arise from the meninges, the protective layers surrounding the brain and spinal cord. Many grow slowly and are noncancerous, but they can still cause problems if they press on nearby brain tissue, nerves, or the spinal cord. A meningioma may affect people of any age, although it is more common in adults. Some are found incidentally during brain or spine imaging done for another reason.

Meningioma symptoms vary based on the tumor’s size and location. Some people have no symptoms, especially when a tumor is small or grows slowly, while others develop problems as the tumor affects nearby brain tissue, cranial nerves, or spinal structures.

Meningiomas develop when cells in the meninges grow abnormally and form a tumor. The precise cause of most meningiomas is not known. Researchers have identified some genetic and environmental associations, but having one of these factors does not mean a person will develop a meningioma.

Risk factors are associations, not guarantees that someone will develop a meningioma. Many people with meningiomas have no identifiable risk factor, and researchers are still studying why these tumors form.

Even a benign meningioma can cause serious problems if it presses on the brain, spinal cord, or cranial nerves. More aggressive tumors may grow faster, invade nearby structures, or return after treatment. The effects depend largely on the tumor’s location, size, growth, and grade.

Evaluation usually begins with a medical history and neurologic examination. Magnetic resonance imaging (MRI) of the brain or spine, often with contrast, is the main imaging test and can show the tumor’s size, location, and relationship to nearby structures. Computed tomography (CT) may be used when MRI is not available or to assess bone involvement. Imaging can strongly suggest a meningioma, although it does not always establish the tumor’s exact grade.

Clinicians consider the tumor’s size, location, growth, symptoms, and suspected behavior when making a diagnosis and treatment plan. A tissue sample may be obtained during surgery when a definitive diagnosis or tumor grade is needed. The grade helps describe how the cells look and how aggressively the tumor may behave.

Meningioma treatment may include active monitoring, surgery, radiation therapy, or a combination of approaches. The choice depends on symptoms, tumor growth, size, location, grade, overall health, and the risks of treatment.

Active monitoring

Active monitoring may be appropriate for a small, slow-growing, or asymptomatic meningioma. The care team uses repeat MRI scans and clinical visits to watch for growth or new symptoms. Treatment may be recommended if the tumor enlarges, begins causing symptoms, or becomes more difficult to manage safely.

Meningioma surgery aims to remove as much of the tumor as can be removed safely. Surgery may help relieve pressure, prevent further growth, and provide tissue for diagnosis and grading. Recovery varies with the tumor’s location and the procedure, and complete removal is not always safe when the tumor is close to important nerves, blood vessels, or brain tissue.

Radiation therapy

Radiation therapy may be used for residual or recurrent tumors, tumors in difficult-to-reach locations, or higher-grade meningiomas. Focused stereotactic treatment delivers radiation to a defined area, while fractionated radiation gives smaller doses over several sessions. Supportive care can help manage symptoms and recovery, and some people may be eligible for clinical trials through a specialist neuro-oncology team.

Many meningiomas have a favorable outlook, but prognosis depends on the tumor’s grade, location, size, growth rate, symptoms, extent of removal, and whether it returns. A person’s overall health and response to treatment also influence the long-term plan.

Follow-up imaging is important because a tumor can grow or return even after treatment. A benign meningioma can still become dangerous because of its location or pressure effects, so the word benign does not guarantee a harmless course. Doctors can discuss an individual’s outlook more accurately after reviewing imaging, pathology, treatment response, and ongoing symptoms.

Contact a healthcare professional about persistent or worsening headaches, seizures, vision changes, weakness, numbness, balance problems, personality changes, or other new neurologic symptoms. Prompt evaluation can help identify whether symptoms are related to a meningioma or another condition.