Meningiomas are brain tumors that begin in the meninges, the membrane that surrounds the outer part of the brain and spinal cord. Most meningiomas are benign; however, even benign tumors in the brain can cause serious problems as they grow and put pressure on other parts of the brain. Meningiomas are the most common of the adult brain tumors that originate in the brain, rather than spreading (metastasizing) into the brain.
The risk of these tumors increases with age – they usually affect people between the ages of 40 and 70, and are very rare in children. They occur about twice as often in women as in men.
Risk factors include previous exposure to radiation and certain genetic disorders, including neurofibromatosis type 2 (Nf2). Some experts believe that people with previous trauma, such as skull fractures are more prone to developing meningiomas.
Meningiomas may cause seizures, headaches, memory problems, vision loss, and arm or leg weakness. Because they often grow slowly, symptoms do not always appear right away, making it difficult to diagnose meningiomas early.
Treatment varies depending on where the tumor is located and what symptoms it is causing. Often, small tumors that aren't causing symptoms can be watched, until treatment is deemed necessary. Some tumors can be surgically removed, resulting in a cure. Other treatments may require surgery accompanied by radiation, or radiation alone. Chemotherapy may be an option in some cases but its efficacy has not been proven.