Nervous System Tumors
individuals with Neurofibromatosis Type 2 (NF2) develop many nervous system tumors that may require treatment. Since the tumors grow slowly, they may be present for many years before causing symptoms. For that reason, NF2 should be evaluated at least annually for tumors, hearing and cataract formation. The optimal and recommended approach involves evaluation by a multidisciplinary team of specialists who can provide a diverse and expanded-level of expertise on this condition.
Vestibular schwannomas are tumors that develop on the eighth cranial – nerves that carry hearing and balance signals from the ears to the brain. Almost all individuals with NF2 will develop these tumors, which are commonly seen on both sides.
The eighth cranial nerve contains two portions – the vestibular portion is important for balance and the acoustic portion is responsible for hearing. For this reason, some of the earliest symptoms relate to dysfunction of the eighth cranial nerve, which includes hearing loss, ringing in the ears (called tinnitus) and problems with balance. These tumors can be detected by magnetic resonance imaging (MRI) of the brain.
In addition to tumors on the eighth cranial nerve, people affected with NF2 can develop other nervous system tumors, called schwannomas, which may develop on other nerves in the body. The symptoms of a schwannoma will depend on the location of the tumor. For instance, schwannomas growing on nerves near the spinal cord may cause numbness or weakness of a part of the body, like the arm or the leg. Schwannomas may also grow on small nerves in the skin appearing as a small bump. These superficial schwannomas rarely cause neurological problems, but they may rub on clothing or be cosmetically disfiguring.
The second most common tumor in NF2 is the meningioma tumor that grows from the lining around the brain, causing pressure on the brain or spinal cord. While most are benign (non-cancerous), they may cause neurologic symptoms including headache, seizures and weakness.
Other tumors in NF2
Less commonly, people with NF2 may develop other tumors affecting the brain or spinal cord including ependymomas, tumors growing on the lining of the spinal cord and brain. These tumors can cause neurological symptoms, depending on their location.