Neurofibromatosis Type 1 (NF1) and PN Tumor Complications

Neurofibromatosis type 1 (NF1) is a congenital disorder (condition present at birth) that causes skin growths, patches of skin discoloration, and tumors throughout the nervous system. Plexiform neurofibroma (PN) is a specific type of NF1 tumor that affects nerves outside the brain and spinal cord, often causing a visible bump in the skin.

A neurofibromatosis plexiform neurofibroma (NF1-PN) can grow on any group of nerves in the body. Its effects may include pain, weakness, and many other symptoms that correspond to the location of the tumor.

Symptoms can range in severity, and treatments and may include medications to shrink the tumor or surgical removal of the tumor.

This article will discuss neurofibromatosis type 1, its complications in children and adults, and treatment.

NF1-PN Complications in Childhood

A person with NF1 could have one or more PNs, and some may cause symptoms, while others might not cause any noticeable effects. Approximately 30% to 60% of people with NF1 have one or more NF1-PNs.

For children, the effects of NF1-PN can substantially impact quality of life and interfere with healthy growth and development. The complications of these tumors are determined by their location.

Symptoms and complications of NF1-PN during childhood include:

• Abnormalities in the development of affected areas of the body
• Bumps on the skin
• Impaired bone growth
• Impaired coordination
• Pain
• Vision changes
• Weakness of the affected area

Due to the effects of PN tumors, young children may delay achieving motor skill milestones. Sometimes, an NF1-PN can prevent a child from developing the skills controlled by the affected nerves. In addition to the direct physical effects of the tumor, children and adults may feel self-conscious about the physical appearance of a PN.

Complications Continued Into Adulthood

Adolescents and adults with NF1 can develop new symptoms of NF1-PNs or experience persistent symptoms of NF1-PNs that started during childhood. Over time, if these tumors are not treated, they may grow larger and could potentially cause increasing symptoms.

While NF1-PN tumors are usually benign, in rare instances, they can become malignant (cancerous).

Symptoms and complications of NF1-PN during adulthood may include:

• Weakness
• Sensory changes
• Pain in the area of the tumor
• Bumps on the skin
• Vision changes
• Loss of hearing
• Shape changes the affected part of the body
• Difficulty breathing
• Trouble swallowing
• Bladder problems, such as urinary tract infections
• Digestive issues, such as bowel obstruction or abdominal pain

Many of these symptoms can begin during childhood, but in some cases, they may begin during adolescence or adulthood as the tumor enlarges.

NF1-PN Symptom Changes

Because NF1 is a lifelong disorder that begins during childhood, the symptoms and the impact on quality of life can continue to evolve and change throughout adolescence, young adulthood, and advanced age.

If you or your child is diagnosed with this condition, it’s important that you work with healthcare providers who can help you understand what to expect in each life stage.

The condition itself may change with an increasing number of growths and tumors.

Awareness in Anticipation of NF1-PN Complications

It’s not possible to anticipate with exact certainty how severe your course of NF1 will be over time, but having an idea of which symptoms to look out for can be helpful.

Make sure you talk to your healthcare provider if you start to experience any new symptoms, such as pain, numbness, tingling, diminished sensation, weakness, or the appearance of a new bump or growth under the skin.

Treatment Options

Surgical removal of NF1-PN can sometimes be curative, but the tumors can recur after they are surgically removed.

Most NF1 tumors are benign, which means they are not expected to invade the body. But benign tumors can cause symptoms due to physical pressure on nearby structures. Usually, benign tumors, such as NF1-PN, are not fatal. However, benign tumors can be life-threatening if they compress vital body structures.

Some NF1 tumors are malignant and can spread and invade the tissues and organs throughout the body. Malignant tumors have a high risk of being life-threatening. Approximately 8% to 13% of people who have NF1 are diagnosed with a malignant tumor.

Inoperable Tumors

Some tumors can be removed surgically while many others cannot due to their location. For example, if a tumor is in a location that cannot be reached surgically or is near a vital structure, it would not be feasible or safe for the tumor to be removed.

Koselugo (selumetinib) is approved by the Food and Drug Administration (FDA) for treating NF1-PN inoperable tumors in children aged 2 and older. This prescription medication is taken twice daily. It works by preventing tumor growth through a biochemical mechanism that inhibits mitogen-activated protein kinase (MAPK), a chemical that promotes tumor growth.

Finding and Communicating With a Neurofibromatosis Specialist and Interdisciplinary Care Team

If you or your child has NF1, it’s important that you seek medical care from a healthcare team that includes a neurofibromatosis specialist, such as a neurologist. Additionally, you may need to see other healthcare providers who can manage the care of some of your complications.

A pain management physician can often provide interventional procedures to help manage pain. A physical therapist can work with you to help you optimize your physical mobility and abilities. An occupational therapist can recommend modifications to your home and working environment and aids to help you with your daily activities.

You may also need to see a surgeon if an assessment may help determine if you would benefit from surgery to remove any of the tumors. A dermatologist can examine your skin growths and discoloration and prescribe treatment, if necessary. An oncologist can provide surveillance and treatment of tumors.

Summary

Living with NF1 can significantly impact your life. This condition begins during childhood and affects the skin and nervous system. Plexiform neurofibromas (PN) are a type of tumor that can grow in the nervous system. They can cause a variety of symptoms, which may include pain, weakness, and bumps on the skin.

These tumors can often be treated surgically. If your child has a PN that is considered inoperable (not able to be treated surgically), they might be prescribed a medication called Koselugo (selumetinib) to help prevent the tumor from growing and causing symptoms.