Schwannomatosis is a condition that results in slow-growing tumors on nerve tissue. The tumors can grow on nerves in the ears, brain, spine and eyes. They also can grow on peripheral nerves, which are nerves located outside of the brain and spinal cord. Schwannomatosis is rare. It's usually diagnosed in early adulthood.
There are three types of schwannomatosis. Each type is caused by an altered gene.
In NF2-related schwannomatosis (NF2), tumors grow in both ears and can cause hearing loss. The altered gene that causes this type is sometimes passed down from a parent. NF2-related schwannomatosis was previously known as neurofibromatosis 2 (NF2).
The other two types of schwannomatosis are SMARCB1-related schwannomatosis and LZTR1-related schwannomatosis. The altered genes that cause these types usually are not passed down through families.
The tumors caused by schwannomatosis usually are not cancerous. Symptoms can include headaches, hearing loss, trouble with balance and pain. Treatment focuses on managing symptoms.
Schwannomatosis symptoms depend on the type.
Symptoms of NF2-related schwannomatosis (NF2) usually result from slow-growing tumors in both ears, known as acoustic neuromas or vestibular schwannomas. The tumors are benign, which means that they are not cancerous.
The tumors grow on the nerve that carries sound and balance information from the inner ear to the brain. These tumors can cause hearing loss.
Symptoms tend to appear during the late teen and early adult years, and can vary. Symptoms may include:
Sometimes NF2 can lead to the growth of tumors on other nerves, including in the brain, spine and eyes. They also can grow on peripheral nerves, which are located outside of the brain and spinal cord. People who have NF2 also may develop other benign tumors.
Symptoms of these tumors can include:
These two types of schwannomatosis typically affect people after age 20. Symptoms usually appear between ages 25 and 30.
SMARCB1- and LZTR1-related schwannomatosis can cause tumors to grow on nerves in the brain, spine and eyes. Tumors also may grow on peripheral nerves located outside of the brain and spinal cord.
Symptoms of SMARCB1- and LZTR1-related schwannomatosis include:
These types of schwannomatosis also can cause tumors to grow in the ear. But it happens rarely, and tumors usually grow in only one ear. This differs from NF2, which causes tumors to grow in both ears. For this reason, people with SMARCB1- and LZTR1-related schwannomatosis don't have the same hearing loss as people who have NF2.
See a healthcare professional if you have symptoms of schwannomatosis. Although there is no cure, complications can be treated.
Schwannomatosis is caused by an altered gene. The specific genes involved depend on the type:
The gene that causes schwannomatosis is sometimes passed down from a parent. The risk of inheriting the gene differs based on the type of schwannomatosis.
For about half of people who have NF2-related schwannomatosis (NF2), they received an altered gene from a parent that caused the disease. NF2 has an autosomal dominant inheritance pattern. This means that any child of a parent who is affected by the disease has a 50% chance of having the gene change. People who have NF2 and whose relatives aren't affected are likely to have a new gene change.
In SMARCB1- and LZTR1-related schwannomatosis, the disease is less likely to be passed down from a parent. Researchers estimate that the risk of inheriting SMARCB1- and LZTR1-related schwannomatosis from an affected parent is about 15%.
Complications can occur in schwannomatosis, and they depend on the type the person has.
NF2-related schwannomatosis (NF2) complications can include:
The pain caused by this type of schwannomatosis can be weakening. People with this type may need surgery or management by a pain specialist.
To diagnose schwannomatosis, a healthcare professional begins with a review of your personal and family medical history and a physical exam. You also may need other tests to diagnose NF2-related schwannomatosis (NF2) or SMARCB1- and LZTR1-related schwannomatosis.
Other tests include:
Treatment for schwannomatosis may include surgery or pain management. You may need regular exams and tests to monitor tumor growth. There is no cure for schwannomatosis.
Surgery or other procedures may be needed to treat serious symptoms or complications.
If tumors become cancerous, they're treated with standard cancer therapies, such as surgery, chemotherapy and radiation therapy. Early diagnosis and treatment are the most important factors for a good outcome.
Managing pain is an important part of treatment for SMARCB1- and LZTR1-related schwannomatosis. Your healthcare professional might recommend:
Researchers are studying medicines that can shrink noncancerous tumors that grow on the hearing and balance nerves in the ears.
Learning you have schwannomatosis may cause a range of emotions. Joining a support group that meets in person or online may help you cope with the emotions you're feeling. Also reach out to family members and friends for support.
You may be referred to a doctor who specializes in brain and nervous system conditions, known as a neurologist.
Here's some information to help you get ready for your appointment.
When you make the appointment, ask if there's anything you need to do in advance, such as fasting before a specific test. Before your appointment:
For schwannomatosis, basic questions to ask include:
Don't hesitate to ask other questions.
Your healthcare provider is likely to ask you several questions, including: