Schwannomatosis

Schwannomatosis is the third major group of neurofibromatosis. It is a rare condition characterized by the formation of multiple nerve sheath tumors (called schwannomas) throughout the body. These tumors do not typically involve the skin and present in adulthood. A major differentiating factor is the absence of vestibular schwannomas, which are characteristic of NF-2. The estimated incidence is 1 in 40,000 or more individuals.

KEY FEATURES FOR DIAGNOSIS

• More than 2 non-skin schwannomas
• No vestibular neuroma on MRI
• No known NF-1 genetic mutation
• Confirmed schwannoma (non-vestibular) and first degree relative who has above findings

Pain is the most common symptom of schwannomatosis. This can affect any part of the body. The pain can be chronic and can range from mild to severe. An organized pain management strategy is often necessary. Pain can even occur in areas where there is no known nerve involvement. Other signs and symptoms depend upon the precise nerves involved. Some of these problems include migraines, numbness, tingling, weakness and paralysis. Life expectancy is normal.

As with the other types of neurofibromatosis, there is a genetic mutation that results in the loss of tumor suppression. The gene is different than NF-1 or NF-2. Most cases of schwannomatosis have no known family history of the condition. Little more is known about this condition other than its similar inheritance pattern to other NF variants.

Genetic testing is not always necessary to make the diagnosis. Symptoms of chronic pain and MRI findings are often enough to have a strong diagnosis.

What to do if you have schwannomatosis

If you or a family member have been diagnosed with schwannomatosis, your first referral is often to a neurologist with expertise in the condition. A pain management specialist may be required to develop a long-term pain control strategy. Depending upon your symptoms and degree of tumor involvement, further referrals may be necessary to a peripheral nerve specialist such as Dr. Panossian. Removing schwannomas from major peripheral nerves requires familiarity with the condition and the workings of the nervous system. Call our office today to find out more.