Schwannomatosis

Schwannomatosis is a group of rare genetic disorders marked by the growth of multiple benign nerve sheath tumors known as schwannomas. These tumors arise from Schwann cells, the cells that form the myelin sheath around peripheral nerves, and they can develop on nerves of the brain and spinal cord as well as on peripheral nerves throughout the body. Depending on location they may cause pain, numbness, weakness and hearing loss. Schwannomatosis belongs to the neurofibromatosis spectrum alongside neurofibromatosis type 1, and it is the least common form of that spectrum, affecting roughly 1 in 20,000 people when NF2-related schwannomatosis is included.