Neurofibromatosis Type 1 (NF1)

Neurofibromatosis type 1 (NF1) is the most common form of neurofibromatosis. It affects your skin and nervous system. Common symptoms include multiple café au lait spots and tumors in your skin and on your nerves. The condition affects each person differently. A healthcare provider can create an individual treatment plan just for your situation.

Overview

What is neurofibromatosis type 1 (NF1)?

Neurofibromatosis type 1 (NF1) is a type of neurofibromatosis, which is a condition that affects your skin and nervous system (brain, spinal cord and nerves). NF1 affects how often certain cells grow in your body. This leads to the formation of benign (noncancerous) tumors. These specifically are nerve tumors called neurofibromas. Tumors form on the nerves in your brain, spinal cord and skin. The most common symptom of NF1 is multiple café au lait spots. Symptoms can also affect your eyes and bones, too.

You might hear your healthcare provider refer to NF1 as Von Recklinghausen disease.

How common is neurofibromatosis type 1?

Neurofibromatosis type 1 is the most common form of neurofibromatosis. It accounts for about 96% of all cases of the condition. NF1 affects an estimated 1 in 3,000 births worldwide annually.

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Symptoms and Causes

What are NF1 symptoms?

Symptoms of neurofibromatosis type 1 happen because of pressure on your nerves. Common signs and symptoms of NF1 include:

  • More than six café au lait spots (birthmarks that appear as flat patches of light to dark brown skin).
  • Two or more neurofibroma tumor growths under your skin. Tumors can appear anywhere in your body. They can be pea-sized or large, soft or firm, often with skin discoloration that’s darker than your natural skin tone.
  • Freckles in your armpits, groin and sometimes underneath your breasts.
  • Growths on your iris (Lisch nodules) or optic nerve (optic glioma) and associated vision problems.
  • Bone growth abnormalities like scoliosis or bowing (curved) leg bones, a large head (macrocephaly) and short stature.
  • Attention-deficit/hyperactivity disorder (ADHD).
  • Pain and difficulty with movement and organ function where tumors grow.

Symptoms can range from mild to severe and happen throughout your life (not all symptoms are present from birth). They affect each person differently.

What causes neurofibromatosis type 1?

A genetic change (mutation) to the neurofibromin 1 gene causes NF1. Neurofibromin 1 gives your body instructions to create the neurofibromin protein. This protein is a tumor suppressor. It manages how often a cell divides and replicates. When your body doesn’t have the proper instructions to create neurofibromin, that means some cells in your body won’t divide and replicate as they should. Instead, they’ll make too many copies of themselves. As a result, tumors form. A tumor is an abnormal cluster of cells that form a solid mass of tissue.

You can inherit the genetic change from one of your biological parents. This is an autosomal dominant pattern of inheritance. But you can also have this genetic change without any family history. Around half of all cases of NF1 occur spontaneously. This means that the genetic change happens randomly, and you don’t inherit it from anyone.

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What are the complications of neurofibromatosis type 1?

Complications of neurofibromatosis type 1 may include:

Some NF1 tumors can develop into cancer.

Diagnosis and Tests

How is NF1 diagnosed?

A healthcare provider will diagnose neurofibromatosis type 1 after a physical exam and testing. During the exam, they’ll look for signs of the condition and learn more about your symptoms.

Tests may include:

For many people, an NF1 diagnosis occurs during adulthood. This happens because symptoms appear in stages as you age. For example, you might be born with café au lait spots (or they appear during the first few years), but freckles might not appear in your underarms or groin area until age 3 to 5. Neurofibromas are common during adulthood. Vision changes usually lead people to visit a healthcare provider to seek a diagnosis.

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Management and Treatment

How is neurofibromatosis type 1 treated?

A healthcare provider can help you manage your symptoms. There isn’t a cure for neurofibromatosis type 1. Treatment varies based on how your symptoms affect you and may include:

  • Tumor removal surgery.
  • Chemotherapy for tumors that develop into cancer.
  • Surgery or support (braces) for bone growth abnormalities.
  • Medications to treat tumor growth (selumetinib).
  • Medications to manage symptoms (like ADHD).

If you have NF1, you should have at least one regular medical check-up every year, along with an annual ophthalmologic (eye) examination. In addition, you should get your blood pressure taken at least once every year to check for complications.

Many people also manage the effects of the condition on their mental health by speaking with a mental health professional or joining a support group.

Are there side effects of the treatment?

Side effects vary based on what type of treatment you need. Your healthcare provider will discuss possible side effects of treatment with you before you begin. For example, side effects of surgery may include bleeding and infection. Side effects of chemotherapy may include hair loss and fatigue.

Prevention

Can neurofibromatosis type 1 be prevented?

There’s no known way to prevent neurofibromatosis type 1. If you plan on starting a family, you can ask a healthcare provider about genetic counseling. This can help you better understand the chances of having a child with a genetic condition like NF1.

Outlook / Prognosis

What is the life expectancy of someone with neurofibromatosis type 1?

Overall, NF1 doesn’t directly affect your life expectancy if your symptoms are mild. Most people experience an average life expectancy. Complications, while less common, may affect your prognosis, especially if you have numerous tumors that can’t safely be surgically removed or if your tumors develop into cancer.

Living With

What can I expect with an NF1 diagnosis?

NF1 affects each person differently. Some people don’t have many symptoms that interfere with their daily lives. Others might have vision problems or pain that affect their movement.

Many people find comfort in speaking with a mental health professional if their symptoms affect their mental health and the way they feel about their bodies. Tumors and birthmarks can grow on areas of your body that other people can see, so you may feel self-conscious about your appearance. A healthcare provider can help you manage these feelings and any symptoms that cause you discomfort.

When should I see a healthcare provider?

Visit a healthcare provider if you notice signs or symptoms of NF1, especially more than six café au lait spots, changes to your skin without a known cause or vision changes. If you’re undergoing treatment for NF1 and experience worsening or severe symptoms like pain, let your healthcare provider know.

You should visit a healthcare provider at least once annually for a check-up to make sure the following NF1-affected parts of your body are functioning as expected:

  • Eyes.
  • Nervous system.
  • Skin.
  • Cardiovascular system.
  • Spine.

What questions should I ask my healthcare provider?

  • What can I expect with an NF1 diagnosis?
  • Could my future children inherit this condition?
  • What type of treatment do you recommend and are there side effects?
  • Can tumors return after removal?
  • How often should I schedule follow-up appointments?

A note from Cleveland Clinic

Neurofibromatosis type 1, the most common type of neurofibromatosis, can affect many different parts of your body, specifically your skin and nervous system. Your symptoms can interfere with your daily routine and how you feel about your body. Your care team can help you find a treatment option that’s right for your situation. You may find comfort in speaking with a mental health professional if your symptoms affect your self-esteem. If you plan on expanding your family and you have a known history of NF1, talk to your provider about genetic counseling.

Medically Reviewed

Last reviewed by a Cleveland Clinic medical professional on 11/29/2023.

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