Genetics Northern California

Neurofibromatosis 2

What is neurofibromatosis, type 2 (NF2)?
How common is NF2?
What causes NF2?
How is NF2 diagnosed?
How is NF2 treated?
Where can I get more information about NF2?

What is neurofibromatosis, type 2?
Neurofibromatosis, type 2 (NF2) is a genetic condition that leads to the growth of benign tumors on the nerves, especially nerves in the ear (vestibular nerve), as well as the brain and spinal cord.  The tumors on the hearing nerves (called vestibular schwannoma or acoustic neuroma), usually affect both ears and cause gradual hearing loss starting in the teens or early twenties.

NF2 is a rare type of neurofibromatosis. There is another type of neurofibromatosis, called neurofibromatosis, type 1 (NF1). NF1 is much more common, but it is a completely different condition. NF1 has a different cause and different symptoms.

Medical concerns in NF2
The tumors in NF2 are not cancerous, but the location on the nerves often affect hearing and balance. Some tumors may lead to paralysis of the facial nerves, numbness in the arms or legs, and fluid build-up in the brain. Individuals with NF2 may also develop cataracts at an early age.

How common is NF2?
NF2 affects fewer than 1 out of every 25,000 people.

What causes NF2?
Neurofibromatosis 2 is caused by a genetic change (mutation) in a gene called NF2, located on chromosome 22. This gene makes a protein that helps controls the growth of certain cells on the nerves, called Schwann cells. When the gene is not working, cell growth is not well controlled, resulting in tumors.

NF2 is an autosomal dominant condition. This means that NF2 affects males and females the same, and a person with NF2 has a 50% chance to pass the gene mutation to a child. Sometimes, a person diagnosed with NF2 has a parent with the condition. However, NF2 can happen for the first time in a family because of a new genetic change, called a "de novo” mutation. This random change happens when the sperm or egg cell is being formed. In these families, neither parent has NF2. This happens in about half of all NF2 cases.

How is NF2 diagnosed?
Hearing loss is often the first symptom, especially when there is no family history of NF2. Finding tumors in both ears is usually enough to make a diagnosis of NF2. However, in a person with a family history of NF2 the diagnosis requires only one of the following features:
1. Tumor in one ear before age 30
2. Any two of the following: spine tumor (meningioma); brain tumor (glioma); nerve tumor (schwannoma); eye clouding or cataracts in childhood

Genetic testing - Genetic testing is not usually needed to diagnose NF2 in a person with multiple tumors. However, it may be considered in someone without tumors when there is a family history of NF2 or in someone with only a few features of NF2.

How is NF2 treated?
The treatment for NF2 mainly focuses on the tumors that might cause medical problems and accommodations for hearing loss, when present. People with NF2 should be followed by a neurologist or neurosurgeon, in addition to their primary provider. Screening for early detection of tumors can start in childhood, or as soon as the diagnosis is known. Surgery and/or radiation may slow the progression of tumors, and may be recommended for some individuals. Medications are being studied to find treatments that could slow or prevent tumor growth. It is also recommended that a person with NF2 have regular hearing tests and eye exams. Kaiser Permanente in Northern California provides specialty care for people with NF2 at the Regional Neurofibromatosis Program

Where can I get more information about NF2?
NIH: Genetics Home Reference on NF2 - General information about NF2 provided as a service of the U.S. National Library of Health. Links to many related sites are included on the page. https://ghr.nlm.nih.gov/condition/neurofibromatosis-type-2

GeneReviews: NF2 – Detailed information about NF2 intended for medical professionals.  https://www.ncbi.nlm.nih.gov/books/NBK1201/
Family Support Resources

Children’s Tumor Foundation: http://www.ctf.org/
Neurofibromatosis Network: https://nfnetwork.org/

Last reviewed: February 15, 2018
Reviewed by: Kimberly Barr, MS, LCGC