Schwannomatosis (shwah-NOH-muh-TOH-sis) is rare. It’s linked to a higher risk of getting a type of tumor called schwannomas. Schwannomatosis affects 1 out of every 25,000 to 40,000 people.

Schwannomas start in the nervous system from cells called Schwann cells. They affect the nerves and often are benign (not cancer). These tumors may cause pain, depending on their location and size.

Neurofibromatosis type 2 (NF2) is now NF2-related schwannomatosis

Neurofibromatosis type 2 (NF2) was renamed NF2-related schwannomatosis in 2022.

The gene mutations of NF2 and schwannomatosis are different. But the symptoms they can cause are similar.

What causes schwannomatosis?

This condition can be caused by a change (mutation or variant) in a gene.

• Some people have mutations in the NF2 gene (chromosome 22). It can be inherited (passed on from parent to child). It also can happen in people whose parents do not have the mutation.
• About half of the people who have schwannomatosis have mutations in the genes SMARCB1 or LZTR1. These mutations can be inherited.

More often, these mutations happen in people who did not inherit these gene mutations from their parents. Doctors are researching other mutations that may cause schwannomatosis.

Signs and symptoms

Schwannomatosis

Schwannomatosis mostly affects areas outside the brain.

It can cause symptoms such as loss of hearing, and problems with balance and swallowing.

It also raises the chances of getting tumors, including:

• Schwannomas, which affect the nervous system. They often affect the vestibulocochlear nerve that controls balance and hearing.
• Meningiomas, a central nervous system tumor that starts in the brain or spinal cord.
• Ependymomas, caused by cancer cells that form in the tissues of the brain and spinal cord.

Schwannomas only appear in SMARCB1- or LZTR1-related schwannomatosis, while all 3 tumors may appear in NF2-related schwannomatosis.

Other common signs and symptoms are:

• Loss of hearing, deafness, or both
• Tinnitus (ringing in the ears)
• Gait instability (hard to walk)
• Weak facial (face) nerve
• Dysphagia (dis-FAY-jee-uh) (hard to swallow)
• Brainstem may be compressed (squeezed)
• Schwannomas can cause numbness, weakness, or pain 

NF2-related schwannomatosis

NF2-related schwannomatosis can affect areas inside and outside the brain. Most often, it affects hearing.

Diagnosis

Schwannomatosis diagnosis

To diagnose schwannomatosis, you may have:

• An imaging test to look for tumors. Most often, the imaging test will be an MRI.
• A physical exam
• A neurologic exam

Not everyone who gets a schwannoma tumor has schwannomatosis.

If you have schwannomatosis related to the genes SMARCB1 or LZTR1, you must have at least 2 schwannomas. To test you for schwannomatosis, you’ll have surgery to remove 1 schwannoma, or a blood test.

We’ll send a sample of the tissue to an MSK pathologist to confirm if you have schwannomatosis. A pathologist is a doctor who uses a microscope to diagnose disease.

NF2-related schwannomatosis diagnosis

One way we diagnose NF2-related schwannomatosis is to look for symptoms. You can have any or all of these symptoms:

Bilateral vestibular schwannomas. These are tumors on both sides of your head. They grow on your hearing and balance nerves.

Meningiomas (meh-NIN-jee-OH-muhs). These tumors are not cancer and grow slowly. They form in the membranes inside the skull that surround the brain and spinal cord.

Ependymomas (eh-PEN-dih-MOH-muhs). These tumors grow in the spinal cord.

Schwannomatosis treatment

The treatment for schwannomatosis depends on your symptoms. Most often, we’ll monitor the tumors. We’ll also manage any pain, neurologic problems, changes in gait, hearing loss, and other symptoms.

If you need treatment, you may have surgery, radiation, or medicine. The treatment plan is based on the kind of tumor you have.

At MSK, you’ll be cared for by our many experts in treating schwannomatosis and the tumors this disease can cause. They will be with you to support you before, during, and after your treatment.

Why choose MSK?

MSK doctors are leading experts in treating schwannomatosis and NF2-related schwannomatosis.

Experts in surgery

Our neurosurgeons are experts in removing complex tumors. The tumor may be in a place that’s hard to reach, or in a delicate part of the body. Our neurosurgeons often can remove tumors that other hospitals consider too complex to remove.

Other surgeons from around the world come to MSK to learn new surgery methods.

MSK surgeons are experts in surgery methods that do less harm to your body. For some people, we may recommend minimally invasive surgery. This method does less harm to your body because it’s done with small incisions (cuts). You recover faster and spend less time in the hospital.

Latest equipment

MSK’s surgical facilities all have the latest equipment available anywhere. Our doctors use the latest imaging technology to monitor tumors.

Experts in managing pain

Pain management is an important part of your care at MSK. We were the first cancer center in the country to have a service just for treating pain in people with cancer.

Our pain experts will help relieve or manage pain after surgery. They can help while you’re still in the hospital, and after you’re home.

We have experts who manage the symptoms and side effects of cancer treatment, such as nausea during chemotherapy.

Our Integrative Medicine Service (also called complementary therapies) offers acupuncture, meditation, massage therapy, yoga, and exercise. 

You may want support to cope with side effects of treatment. These may include pain, fatigue (feeling very tired), nerve problems, nausea, insomnia, and stress. 

Without using prescription drugs, integrative therapies can help improve and control side effects of cancer treatment.

MSK’s research on schwannomatosis

Our neuro-oncologists are leading experts who are exploring important research. Clinical trials are research studies that test new treatments, procedures, or devices to see how well they work. MSK has many clinical trials that are looking at new ways to treat schwannomatosis. 

MSK also is part of the Neurofibromatosis Clinical Trials Consortium (NFCTC). This group gives people with neurofibromatosis access to many clinical trials. Research studies focus on preventing or treating complications (problems) related to the disorder. 

We also work closely with the Children’s Tumor Foundation on research, and connect people with support services.