THURSDAY, DAY 4
THE MIND
Meninges are layers of protective membranes surrounding the brain and spinal cord, and tumors that form in these areas are called meningiomas. They are the most common type of tumor that originates in the brain. Most meningiomas (90 percent) are noncancerous, but they can still be life threatening or cause complications such as vision loss or paralysis by pressing on important parts of the brain or spinal cord.
For a tumor of this type to occur, something—genes, environmental exposure, or a combination of the two—needs to alter the cells in the meninges so that they begin to multiply rapidly. It is common in children who received radiation therapy for leukemia. The condition is also more common in women, which has led scientists to think that female hormones may play a role.
Most people develop a meningioma after age 40, although it’s possible at any age. It is usually a very slow-growing tumor and often doesn’t cause symptoms or require immediate treatment. Doctors can detect a meningioma through a CT scan or MRI of the brain, often after the tumor grows large enough for a patient to experience symptoms, such as seizures, persistent headaches, hearing loss, or muscle weakness. Surgery may be performed, although it’s not always possible to remove the entire tumor if it is in a sensitive area, such as near the eyes. If the meningioma can’t be completely removed, the doctor may opt to administer radiation in an attempt to destroy the rest of the tumor and reduce the risk of recurrence.