Schwannomatosis (SWN)

Neurofibromatosis (NF) is a group of genetic conditions that cause tumours to grow on nerves throughout the body. The main types of NF include neurofibromatosis type 1 (NF1) and schwannomatosis (SWN), which includes NF2-related schwannomatosis (NF2-SWN), formerly known as neurofibromatosis type 2 (NF2).

What Is Schwannomatosis?

Schwannomatosis (SWN) is the least common and most recently defined form of neurofibromatosis. The term schwannomatosis is an umbrella term for several related genetic conditions that cause benign (non-cancerous) tumours, called schwannomas, to develop on nerves.

Schwannomatosis affects approximately 1 in 20,000 people. When NF2-related schwannomatosis (NF2-SWN) is excluded, the remaining forms of schwannomatosis occur in about 1 in 70,000 individuals.

What Causes Schwannomatosis?

Schwannomatosis is caused by changes (pathogenic variants) in genes that help regulate cell growth and division. These genes are located on chromosome 22. Currently, three genes are known to be associated with schwannomatosis:

  • NF2
  • LZTR1
  • SMARCB1

Additional genes may be identified as research advances.When these genes are not functioning properly, cells may grow and divide more than they should, leading to the development of tumours.

Schwannomatosis can be inherited or occur as a spontaneous (new) genetic mutation, and it affects people of all genders, ethnicities, and backgrounds equally.

When Do Symptoms Appear?

Signs and symptoms of schwannomatosis most often develop during the teen or young adult years, though they can appear at any age. The condition can affect people differently, and symptoms may change over time. Schwannomas are benign, meaning they are not cancer.

Common Signs and Symptoms

People with schwannomatosis develop schwannomas on:

  • the central nervous system (brain and spinal cord)
  • Peripheral nerves (nerves throughout the rest of the body)
Symptoms can vary depending on tumour location and may include:
  • Chronic pain (the most common symptom)
  • Hearing loss
  • Balance or coordination issues
  • Eye or vision problems
  • Numbness, weakness, or other nerve-related symptoms
  • Pain may occur anywhere in the body and is thought, at least in part, to result from tumours pressing on nerves.

Pain management is often an important and ongoing part of care.

Is There a Cure?

There is currently no cure for schwannomatosis. However, symptoms and complications can often be managed through:

  • Regular monitoring
  • Pain management strategies
  • Surgery in selected cases
  • Supportive therapies

Promising advances in research are underway, and understanding of schwannomatosis continues to grow.

Living With Schwannomatosis

Schwannomatosis is a lifelong condition, but support can make a meaningful difference. Care is often best managed by healthcare providers familiar with NF and schwannomatosis, and may involve a team of specialists depending on individual needs.

Because British Columbia does not yet have a dedicated multidisciplinary NF clinic, individuals may need support navigating care. We can help.

Support in British Columbia

The Tumour Foundation of BC offers:

  • One-to-one support
  • Help navigating care and understanding options
  • Educational resources
  • Community connection

You don’t have to navigate schwannomatosis alone.

Go to the Resource Centre