Neurofibromatosis type 1 (NF1) is a genetic condition that is usually diagnosed in childhood. It affects around one in 3,000 people. It is considered one of the most common genetic disorders.

NF1 can cause a variety of symptoms and complications. Among the most serious is a predisposition to develop certain types of tumors, including the following:

• neurofibromas of the skin (dermal neurofibromas)
• plexiform neurofibromas (which often involve the spine)
• malignant peripheral nerve sheath tumors (MPNST)
• gliomas
• gastrointestinal stromal tumors (GIST)
• pheochromocytoma
• rhabdomyosarcoma
• breast cancer
• juvenile myelomonocytic leukemia (JMML)

Causes of Neurofibromatosis Type 1 (NF1)

NF1 is caused by a genetic mutation found on chromosome 17. That mutation can be inherited, or it can occur in people without a family history. About half of all people with NF1 inherited the condition from a parent. There is an up to 50 percent chance that someone with NF1 will pass on the mutation to a child.

Neurofibromatosis Type 1 (NF1) Diagnosis

A diagnosis of NF1 is based on whether someone shows signs of the disease. The first step in diagnosising NF1 is often a physical exam to check for these signs. The doctor will also review personal and family medical history. 

A person must have at least two of these signs to be diagnosed with NF1: 

• six or more café au lait spots (flat light brown spots on the skin)
• two or more dermal neurofibromas (small lumps or bumps that grow on or under the skin) or at least one plexiform neurofibroma (a very large neurofibroma)
• bony abnormalities
• a family history of NF1
• Lisch nodules (harmless dots in the colored part of the eye)
• freckles in the underarm or groin area
• an optic pathway glioma (a tumor that grows in the cells surrounding the optic nerve)

To make a diagnosis, an eye exam may be needed to look for Lisch nodules. Imaging tests may be needed to check for tumors or bone problems.

In some cases, a genetic test can help make the diagnosis.

Neurofibromatosis Type 1 (NF1) Treatment

The treatments for NF1 vary from person to person. For most people, the care plan involves monitoring for tumors while managing pain, neurologic problems, and other symptoms. 

At Memorial Sloan Kettering, our goal is to give every child and adult who comes to us for NF1 treatment compassionate, personalized care from a multidisciplinary team of experts. We take a family-centered approach to care so that you feel empowered and confident that you are making the best decisions possible. Your team will include doctors, nurses, and other professionals who are dedicated to caring for adults and children with NF1 and the tumors associated with the disease.

MSK doctors are leading experts in treating NF1-associated tumors. We use the most-advanced imaging technology available to aggressively screen for them. When treatment is needed, we will create a personalized treatment plan based on the precise details of the tumor. 

Our neurosurgeons have particular expertise in removing complicated tumors in hard-to-reach or delicate parts of the body. Many times we can remove tumors that are considered inoperable elsewhere. We use the latest technology, including robotic surgery, as well as minimally invasive approaches whenever possible. This level of specialization can often have a dramatic effect on our patients’ quality of life.
 

Neurofibromatosis Type 1 (NF1) Research

MSK participates in the Neurofibromatosis Clinical Trials Consortium (NFCTC). This group gives people with neurofibromatosis access to a wide array of ongoing research studies focused on preventing or treating complications associated with the disorder. We work closely with the Children’s Tumor Foundation (CTF) to conduct research and connect people with support services.

The Neurofibromatosis Clinic also collaborates closely with several labs at Memorial Sloan Kettering that are conducting NF1-related research. For example, Luis Parada, Director of MSK’s Brain Tumor Center, is developing drugs to treat tumors associated with neurofibromatosis, including gliomas, neurofibromas, and malignant peripheral nerve sheath tumors. Ping Chi, of the Human Oncology and Pathogenesis Program, is studying the genetic and epigenetic changes that lead to the formation of these tumors. Translating their discoveries into patient care is one of the Neurofibromatosis Clinic’s main goals.