Neurofibromatosis

What is Neurofibromatosis?

Neurofibromatosis is a term that describes a group of disorders that involve tumors that grow within the nervous system. These tumors grow in the thin membrane that protects and surrounds the  nerves.

There are three distinct types of neurofibromatosis:

  • Neurofibromatosis type 1 (NF1)
  • Neurofibromatosis type 2 (NF2) and
  • schwannomatosis

Most tumors are benign (non-cancerous) but some do become cancerous. Mutations in genes are the cause of neurofibromatosis and these mutations prevent the normal productions of proteins and cause cells to multiply rapidly and form the tumors.

What are the Symptoms of Neurofibromatosis?

The symptoms of a neurofibromatosis depend on what kind you have.  NF1 is characterized by freckling in the groin or armpit area, scoliosis, abnormal development of the temple bone in the skull or the tibia, a tumor on the optic nerve, and six or more spots on the skin that are light brown and 5 mm or more in width for children and 15 mm or more in width for adults.  There is also usually a parent or sibling in the family that also has NF1.

NF2 and schwannomatosis symptoms include a parent or sibling with NF2 and a schwannoma that appears before age 30 and two of these: meningioma, juvenile cataracts, glioma, or schwannoma. With shwannomatosis, shwannomas appear all over the body and pain is a major symptom. Numbness, weakness, and tingling are other symptoms that may occur.

Neurofibromatosis Causes

A genetic neurological disorder, Neurofibromatosis is caused by specific mutations to single chromosomes in the patient. The disease manifests itself through tumors that grow on and around the body’s nerves or underneath the patient’s skin. There are three types of Neurofibromatosis. NF1 is the most common form occurring in somewhere between 1 in every 3000 to 4000 births. The chromosome affected in NF1 is chromosome 17. Most patients with NF1 have mild symptoms and can live with very little treatment. NF2 is more unusual and appears only in roughly 1 out of every 40,000 births. NF2 is caused by a genetic mutation to chromosome 22. It is directly linked to more serious health issues, particularly acoustic neuromas which can lead to hearing loss. NF 2 does require treatment, often surgical, and can negatively impact the life of the patient in ways that NF 1 does not. A third type of Neurofibromatosis is called Schwannomatosis, and its genetic origins are not known. The tumors developed in this condition can cause severe pain, numbness and tingling of affected areas. All forms of Neurofibromatosis seem to affect men and women of all races equally, although the different types develop in different age ranges. NF1 tends to develop in childhood, while the onset of NF2 is more likely to happen in early adulthood.

How is Neurofibromatosis Treated?

Treatment is difficult because scientist have been unable to come up with a definitive way to keep neurofibromas from growing.  Surgery is one of the recommendations, especially if they believe it may become cancerous or if they are likely to cause disfigurement.  There are several options for surgery but there is no “best” type of surgery that can be agreed upon.  Radiation and chemotherapy may also be considered if it is cancerous.

Other treatments focus on managing the symptoms of neurofibromatosis.  Medications can be prescribed to treat seizures or headaches.

Neurofibromatosis Prevention

In terms of prevention, because the disease is caused by genetic mutation, there is not a clear measure or behavior that people can adopt to avoid the development of Neurofibromatosis. NF1 and NF2 seem to be autosomal in nature, so families that know they carry the mutation and have a family history of the disease can avoid having children or use donor eggs or sperm to prevent transmission of the defective genes. Those at risk of carrying the mutation could pursue DNA testing to make sure both parents are not affected as that raises the risk of developing Neurofibromatosis in their child to over 50%.

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Last Reviewed:
October 07, 2016
Last Updated:
January 25, 2018