Schwannomatosis is a rare genetic condition that causes the development of non-cancerous (benign) tumors along nerves in the body. Schwannomatosis is one type of neurofibromatosis (NF), which is a group of genetic conditions that cause abnormal cell growth in nerve tissues throughout the body. This condition causes non-cancerous (benign) tumors to develop in special cells that surround nerves (Schwann cells). These tumors, called schwannomas, develop around nerves that come from the brain (cranial), are in the spine (spinal), and that connect the brain and spine (peripheral). Unlike another form of NF, known as neurofibromatosis type 2 (NF2), schwannomatosis does not cause tumors to form in the nerves between the ear and brain (vestibular schwannomas). This means people with schwannomatosis typically do not have hearing loss. Symptoms of schwannomatosis depend on the location of the tumors, but can include chronic pain, numbness, tingling, and weakness.
The genetics of schwannomatosis are not well understood. Some cases of the condition are believed to be caused by a change (mutation) in the SMARCB1 gene. The diagnosis of schwannomatosis is considered in people who have schwannomas in any area of the body that does not include the inner ear. Genetic testing may be used to confirm the diagnosis. There is no cure for schwannomatosis, but surgery to remove schwannomas may be helpful if a person has significant symptoms. If your child has been diagnosed with schwannomatosis, talk to their doctor about all treatment options. Additional information and support are available through schwannomatosis support groups.