What is Neurofibromatosis (NF)?
Neurofibromatosis (NF) is a genetic disorder affecting nerve cell growth and development. It is characterized by the development of benign tumors called neurofibromas on nerve tissue and other symptoms.
There are three types of neurofibromatosis: NF1, NF2, and Schwannomatosis. NF1 is the most common type of neurofibromatosis and is caused by a mutation in the NF1 gene. The condition is inherited in an autosomal dominant manner, meaning that an affected individual has a 50% chance of passing the mutation on to each of their children.
NF2 is caused by a mutation in the NF2 gene. The condition is inherited in an autosomal dominant manner. Schwannomatosis is caused by a mutation in either the SMARCB1 or LZTR1 gene. It is also inherited in an autosomal dominant manner.
Symptoms
Each type of neurofibromatosis can have somewhat different symptoms. Some of these symptoms can include:
- Skin pigment changes
- Multiple cafe-au-lait spots on the skin
- Multiple neurofibromas (tumors that develop along nerves) in multiple areas of the body
- Bone abnormalities
- Pain
- Weakness
The tumors associated with neurofibromatosis are non-cancerous (benign), but some may have an increased cancer risk. Where the neurofibromas develop and how large they become can lead to other symptoms.
Diagnosis
The diagnosis of neurofibromatosis is based on clinical symptoms and evaluation of the tumors. Genetic testing can confirm the diagnosis. Imaging studies such as MRI or CT scans can also be used to evaluate the size and location of tumors.
Treatment
Treatment for neurofibromatosis depends on the type and severity of the symptoms. In some cases, no specific treatment may be needed other than observation.
For others, surgery may be used to remove tumors causing pain or other problems.
In 2020, medication was approved to treat NF1 in children over 2 with certain types of tumors. The medication, Koselugo, works by blocking an enzyme the tumors need to grow.