"Schwannomatosis" – What Is It?

Schwannomatosis is a recently identified rare neurofibromatosis, also known as neurofibromatosis type 3. The disease leads to the development of benign nerve sheath tumors, called schwannomas, which can form anywhere along spinal and peripheral nerves. These schwannomas can cause chronic and often diffuse pain. Schwannomatosis is usually not diagnosed until adulthood.

Overview of the Chapters on This Page:

  • What Is the Risk of Cancer?
  • What Is Known About the Development of "Schwannomatosis"
  • Is There Any Treatment Available?
  • Medical Measures for Early Detection
  • Schwannomatosis – What You Can Do Yourself
  • Links and Further Information (e.g., From Support Groups)
  • What Is the Risk of Cancer?
  • Is There Any Form of Treatment Available?
  • Medical Measures for Early Detection
  • Schwannomatosis – What You Can Do Yourself
  • Links (e.g., From Support Groups) and Further Information

How Is "Schwannomatosis" Diagnosed?

Most patients present to the doctor because of chronic pain in adulthood (median age at onset of symptoms 30 years, median age of diagnosis 40 years). During the clinical or imaging examination, the schwannomas, which can compress or displace the nerve due to their location and cause pain, become apparent. However, the localization of pain and the location of the schwannomas do not always correlate well. Also, the tumor burden does not always explain pain intensity and frequency. Although pain is the most common and usually the only complaint, schwannomas can cause other neurological symptoms such as numbness, paresthesia, bladder and rectal dysfunction, visual disturbances, and headaches, depending on their location.

A specific form of schwannomatosis can present clinically with symptoms of intracranial pressure, such as headaches and fasting vomiting (vomiting at night or early in the morning upon waking). In these cases, meningiomas are identified as the cause. Neurological deficits arise depending on the tumor’s location. This form is also known as meningiomatosis.

Clinical Diagnostic Criteria

  • Evidence of more than 2 schwannomas not located in the skin, at least one of which has been confirmed by tissue examination
    and
    without evidence of bilateral vestibular schwannomas (a benign tumor of the nerve sheath of the VIII cranial nerve, the auditory balance nerve) in imaging from the head or brain. cranial nerve sheath, the auditory balance nerve) on imaging of the head
    or
  • Existence of a schwannoma confirmed by tissue examination or an intracranial meningioma (usually a benign tumor of the meninges)
    and
    a first-degree relative (biological parents or children) with schwannomatosis

However, if there are more than 2 schwannomas not located in the skin without tissue examination confirmation, the suspected diagnosis of schwannomatosis is obvious, especially if there is chronic pain.

Segmental schwannomatosis describes the occurrence of schwannomas in only one extremity or limited to 2 spinal segments (30% of patients have segmental schwannomatosis).

What Is the Risk of Cancer?

Depending on the localization of the genetic changes, schwannomatosis presents in 3 clinically different forms:

  • SMARCB1 schwannomatosis is associated with the development of many often painful but benign tumors of the nerve sheaths of peripheral or central nerves (located in the head or spinal canal). The risk of malignant degeneration is probably slightly increased. In addition, the risk of developing benign meninges (meningiomas) tumors is risen somewhat (5%).
  • LZTR1 schwannomatosis can cause unilateral tumors of the eighth cranial nerve, the auditory, vestibular nerve (vestibular schwannomas).
  • Meningeomatosis(SMARCE1 schwannomatosis) predisposes to isolated central or spinal benign tumors of the meninges (meningiomas) in childhood.

What Is Known About the Development of "Schwannomatosis"?

Schwannomatosis is a comparatively rare genetic disease (less than 1 affected person in 40,000) in which the regulation of cell growth in the nervous system is lost due to changes in the genetic material (mutations). There is a loss of control over cell proliferation, so Schwann cells, which form an insulating sheath around the nerve fibers, divide excessively, and schwannomas can develop. Schwannomatosis often appears sporadic, with a familial clustering described in only around 20 percent of cases.

Is There Any Form of Treatment Available?

There is currently no known specific treatment for schwannomatosis. Surgical intervention may be indicated in certain situations and should be performed by a doctor familiar with the disease. For inoperable schwannomas that cause clinical symptoms such as pain, good pain therapy is often the only treatment option.

Please ask your treating physician whether any open clinical trials might suit you.

Diagnosis of " Schwannomatosis" What's Next?

If you have been diagnosed with this cancer predisposition syndrome, it is important to see a specialist. The following section explains whether cancer screening tests or other measures are needed and how they should be carried out. We also give you some valuable tips on what you can do yourself. If you have any questions, please do not hesitate to contact us or your doctor.

Diagnosis of " Schwannomatosis" What's Next?

If you have been diagnosed with this cancer predisposition syndrome, it is important to see a specialist. The following section explains whether cancer screening tests or other measures are needed and how they should be carried out. We also give you some valuable tips on what you can do yourself. If you have any questions, please do not hesitate to contact us or your doctor.

Medical Measures for Early Detection

Patients with schwannomatosis should be screened for life, starting from the time of diagnosis, by the following recommendations (AACR 2016).

SMARCB1 Schwannomatosis

  • Baseline MRI (head and spinal canal) at diagnosis, then every 2-3 years from the age of 10 or more frequently depending on the clinical picture
  • Whole-body MRI if necessary

LZTR1 Schwannomatosis

  • Baseline MRI (head and spinal canal) at diagnosis, then every 2-3 years from the age of 15-19 or more frequently depending on the clinical picture
  • Consider whole-body MRI

SMARCE1 Schwannomatosis

  • Neurological examination
  • Baseline MRI (head and spinal canal) annually from diagnosis until the age of 18, then every 3 years if the clinical findings are normal
  • Shorten interval in case of tumor detection or clinical symptoms

Schwannomatosis – What You Can Do Yourself

You Should Pay Attention to This

Please get in touch with your treating physician or any neurofibromatosis consultation and make an appointment as soon as possible if you experience new symptoms such as headaches, visual disturbances, or other neurological deficits.

Further Information

Any further questions?

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