Neurofibromatosis

Neurofibromatosis is a condition in which nerve tumors grow throughout the body. At the Spine Hospital at the Neurological Institute of New York, we specialize in treating nerve tumors in the spine.

Three types of neurofibromatosis have been identified. Two of them, neurofibromatosis I (NF1) and neurofibromatosis II (NF2), are the subject of this page. The third type is schwannomatosis.

Symptoms

Symptoms of NF1 include light tan spots on the skin, freckles under the arms or in the groin, changes in the bones or in the irises of the eyes, and the formation of nerve tumors called neurofibromas. Neurofibromas are usually benign (noncancerous) tumors. Only about 5% of NF1 patients develop spinal tumors that cause them symptoms. Many more have spinal tumors that do not cause symptoms.

Symptoms of NF2 include tinnitus (ringing or buzzing in the ears), hearing loss, balance problems, and tumors (meningiomas, ependymomas, and schwannomas), which are usually benign. People with NF2 are much more likely than those with NF1 to develop symptomatic spinal tumors.

Most tumors associated with neurofibromatosis are benign. But even benign tumors can cause problems when they compress the spinal nerve roots or spinal cord. Symptoms of nerve root and cord compression include pain, changes in sensation (numbness, tingling), changes in movement (clumsiness, weakness), or difficulty controlling bowel or bladder. Patients with neurofibromatosis should consult a professional promptly if they experience any of these symptoms.

Diagnosis

Neurofibromas, schwannomas, and meningiomas can be identified on MR (magnetic resonance) and CT (computed tomography) scans. MR scans use magnets, radio waves, and computer technology to produce images of organs and tissues like the brain and spinal cord. CT scans use a combination of X-rays and computer technology to produce detailed images of bones and soft tissues.

Risk Factors

Each type of neurofibromatosis is caused by a mutation in a specific gene. These mutations can be inherited from a parent or can arise spontaneously at conception.

NF1 and NF2 are inherited in an autosomal dominant pattern, which means that an affected parent has a 50% chance of passing the gene on to each of his or offspring. Schwannomatosis has a more complicated pattern of inheritance; the chance of an affected parent passing it on to each offspring is about 15%.

Treatments

The treatment of the tumors caused by neurofibromatosis depends on the size, location, and symptoms of the tumors. Small tumors in patients with no symptoms can often be observed over time with yearly MR.

For larger or symptomatic tumors, or tumors showing growth over time, surgical removal is usually recommended. In most patients, complete removal of these tumors can be safely achieved using a surgical microscope, very fine instruments, and an array of microsurgical techniques.