Your are here: Home > Diseases, Conditions & Injuries > Neurofibromatosis

Neurofibromatosis

Definition

Neurofibromatosis (NF) is a genetic disorder of the nervous system. It causes tumors to grow on the nerves in any part of the body. Neurofibromatosis can also produce other abnormalities, such as changes in the skin and deformed bones.

There are two types of neurofibromatosis, NF1 and NF2. They are caused by mutations of different genes. NF1 is more common.

Causes

Neurofibromatosis is caused by an abnormal change in a gene, called a genetic mutation. In many cases the abnormal gene is inherited. However, a minority of cases occurs when the gene changes by chance in a person with no family history of the disease. A person with the inherited form of neurofibromatosis has a 50% chance of passing on the abnormal gene each time he or she has a child.

Risk Factors

A risk factor is something that increases your chances of getting a disease or condition. The only risk factor for neurofibromatosis is having a family member with the disease.

Symptoms

NF1 and NF2 have different symptoms. With either type, the symptoms can range from mild to severe. In most cases the symptoms are mild.

Symptoms of NF1

A person with NF1 has two or more of the following symptoms:

Five or more light brown spots (called café-au-lait spots) on the skin
Neurofibromas – tumors that grow on a nerve or nerve tissue
Freckles in the armpits or groin
Growths on the iris (colored part of the eye)
Tumor on the optic nerve that may affect vision
Severe scoliosis (curved spine)
Deformed or enlarged bones other than the spine

Most of these symptoms begin between birth and age 10. Neurofibromas rarely occur before puberty.

Symptoms of NF2

A person with NF2 has several tumors on the nerves of the brain and spine. Most common are tumors that affect the nerves to the ears. Hearing loss may begin as early as the teen years.

Other symptoms may include:

Tinnitus (ringing in the ear)
Poor balance
Headaches
Pain or numbness in the face

Diagnosis

The doctor will ask about your symptoms and medical history, and perform a physical exam. Neurofibromatosis is diagnosed based on symptoms. If necessary, the diagnosis can be confirmed by genetic testing. In a person with a family history, genetic testing can also identify a neurofibromatosis gene before symptoms occur.

Treatment

Treatments for both types of neurofibromatosis are aimed at controlling symptoms that cause problems. Neurofibromatosis tumors are not always treated because they grow slowly, are rarely cancerous, and may not cause problems. People with neurofibromatosis need to have regular exams to check for changes in:

Tumors
Brown spots on the skin
Bones, including scoliosis
Hearing
Vision

Treatment of NF1

Surgery can help correct some bone abnormalities. Bone surgery may be combined with back braces to treat scoliosis. Surgery can also be used to remove painful or disfiguring tumors. However, tumors may grow back and in larger numbers. In rare cases when tumors become cancerous, treatment may include surgery, chemotherapy, or radiation.

Treatment of NF2

Surgery can remove tumors, but it may damage the nerves. If the nerves to the ears are damaged, hearing loss can occur. Other treatment options include partial removal of tumors and radiation. MRI scans of the brain can locate tumors when they are small so treatment can be started early.