Neurofibromatosis

What is neurofibromatosis?

Neurofibromatosis (NF) is a nervous system disease that causes skin defects and tumors on nerve tissues. It can also lead to other problems. The condition may cause mild symptoms or worsen over time. Although there is no known cure, treatment can help control symptoms.

The nerve tissue tumors begin in cells that protect nerves. These tumors can vary in size and can occur anywhere in the body, including the skin, inner ear, brain, and spinal cord. Most are not cancerous, although some may develop cancerous changes.

The most common type of tumor is called a neurofibroma. This is a noncancerous growth that usually develops on or under the skin. The other common type of tumor is called a schwannoma. These growths form in cells that help insulate nerves.

NF is a genetic disorder. Genetic disorders are caused by changes (mutations) in genes.

Symptoms of neurofibromatosis

There are different types of NF. The signs and symptoms differ depending on the type.

Neurofibromatosis type 1

Symptoms of NF1 include:

• harmless, flat, light brown spots (cafe-au-lait spots) that appear at birth or during early childhood
• noncancerous tumors (neurofibromas) that typically grow close to the skin but may also occur deeper in the body (commonly occuring between ages 10 and 15)
• freckles in the armpit, groin, and other skin folds
• clumps of pigment in the colored portion of the eye
• a tumor on the nerve that connects the eye to the brain
• bone or skeletal problems, such as bowed legs or curvature of the spine
• learning disabilities, hyperactivity
• speech and vision problems
• headaches and seizures
• oversized head in children
• short stature
• high blood pressure.

The symptoms of NF1 tend to get worse over time.

Neurofibromatosis type 2

People with this disorder typically develop slow-growing, noncancerous tumors on a specific nerve in the brain. Early symptoms usually involve hearing and balance problems. Some people also develop cataracts. Some develop other kinds of tumors.

Symptoms of NF2 include:

• hearing loss, often in both ears
• ringing in the ears
• problems with balance, dizziness
• weakness, numbness, or tingling in an arm or leg
• vision problems such as cataracts (clouding of the eye's natural lens)
• facial numbness
• problems with speech and swallowing
• frequent and persistent headaches
• seizures.

Schwannomatosis

This disorder causes noncancerous tumors on nerves of the brain and spinal cord and nerves in the arms and legs. Symptoms include intense pain that can occur in anywhere in the body. The pain is caused by tumors pressing on nerves or tissue. Numbness or tingling in the fingers and toes can also occur.

Diagnosing neurofibromatosis

Test for NF usually include:

• Complete physical and medical history. Your doctor checks for general signs of disease, health habits, and past illnesses and treatments. The doctor will also ask what medical conditions family members have or have had.
• Imaging studies. These include x-ray, ultrasound, magnetic resonance imaging (MRI), and computed tomography (CT) scans, to look for tumors or other problems.
• Biopsy. This test looks at small pieces of tumors under a microscope.
• Genetic testing. Blood tests can confirm if a person has NF1 or NF2. Sometimes family members are tested too.
• Skin exam. Your doctor can use special lamps to look for cafe-au-lait spots (for NF1).
• Ear exam and hearing test, especially those with NF2.

To determine if a person has NF1, doctors look for at least two of the following:

• six or more cafe-au-lait spots
• neurofibromas
• freckles in the armpit or groin
• pigment clumps in the eye
• a tumor on the optic nerve
• bone problems in the spine, skull, or leg
• a parent, sibling, or child with NF1.

To determine if a person has NF2, doctors look for tumors on certain balance and hearing nerves. They also look for

• a family history of the disease
• certain eye tumors
• cataracts that start during childhood.

Although the skin problems connected with NF1 often appear at birth or shortly afterwards, other symptoms typically don't appear until later. With NF2, tumors grow slowly and may not be found for many years — usually during the teens and early 20s.

Preventing neurofibromatosis

NF occurs when a gene suddenly changes. Right now, there is no way to prevent this disease. With NF1 and NF2, a parent with an abnormal gene has a 50% chance of passing it on to each of their children. Tests can be performed during pregnancy to determine whether a fetus carries the defective gene.

Treating neurofibromatosis

Treatment for NF depends on

• the patient's age, health, and medical history
• the symptoms
• which nerves are affected
• the expected progression of the disease.

Although there is no known cure for NF, surgery and other treatments can help to relieve symptoms. A person with NF may have several medical specialists to treat the disease.

Neurofibromatosis type 1

• Tumors: Surgery may remove painful or disfiguring growths. However, tumors may grow back and in greater numbers.
• Optic tumors: Treatment options include surgery, radiation, and chemotherapy. It can be difficult to remove these growths. Surgery may harm vision.
• Curvature of the spine: Surgery or a back brace may be used.
• Cancerous tumors: These are rare. Treatment options include surgery, radiation, and chemotherapy.
• Headache and epileptic seizures: Medication can help.

Children with NF1 should have a thorough neurological exam before entering school because of the higher-than-average risk for learning disabilities. Parents and teachers of children already in school should watch for learning problems.

Neurofibromatosis type 2

Surgery, radiation, and monitoring are the three main treatment approaches.

• Surgery: There are several surgical options for removing growths and cataracts, as well as for other eye problems.
• Radiation: A special type of surgery that uses radiation is an option in some cases. Radiation can help limit a tumor's growth.
• Monitoring: For some patients, it may be best to simply follow the growth of tumors until treatment is needed. This is called active surveillance. Patients with NF2 should have an annual neurological checkup. It is also wise to get thorough eye and hearing exams each year.

Schwannomatosis

Surgery to remove tumors can help ease pain, although the pain may return if new tumors form. Specialized doctors can help with pain management.

When to call a professional

Contact your doctor if you or your child has symptoms of NF.

Prognosis

NF progresses differently for each person. It is hard to predict the course of the disease. A person's prognosis depends on the types and locations of tumors that he or she develops.

Neurofibromatosis type 1: Most people will have mild to moderate symptoms that may worsen over time. Patients can live normal and productive lives. In some cases, however, NF1 can affect quality of life.

Neurofibromatosis type 2: These tumors generally grow slowly. Balance and hearing may become worse over time. Sometimes tumors grow next to vital structures such as the brain. If they are not treated, this situation can be serious.

Schwannomatosis: Some patients have mild pain, but many have significant pain that can be challenging to control.

Additional info

National Institute of Neurological Disorders and Stroke
https://www.ninds.nih.gov/

Neurofibromatosis Network
https://www.nfnetwork.org/