Schwannomatosis

Schwannomatosis (SWN) is a group of rare genetic disorders characterized by the development of multiple benign nerve sheath tumors called schwannomas. These tumors arise from Schwann cells, which form the myelin sheath surrounding peripheral nerves. Schwannomatosis is part of the broader group of conditions collectively referred to as NF, which includes neurofibromatosis type 1 (NF1) and all forms of schwannomatosis, including NF2-related schwannomatosis (NF2-SWN), previously called neurofibromatosis type 2.<ref name="Plotkin2022">{{cite journal |last1=Plotkin |first1=Scott R. |last2=Blakeley |first2=Jaishri O. |last3=Evans |first3=D. Gareth |title=Updated diagnostic criteria and nomenclature for schwannomatosis |journal=Genetics in Medicine |year=2022 |doi=10.1016/j.gim.2022.01.013}}</ref><ref name="GeneReviews">{{cite web |title=Schwannomatosis |url=https://www.ncbi.nlm.nih.gov/books/NBK487394/ |publisher=GeneReviews |access-date=2026}}</ref>

Schwannomatosis is considered the least common form within the neurofibromatosis spectrum. It affects approximately 1 in 20,000 individuals, with NF2-related schwannomatosis representing the most common subtype. When NF2-related schwannomatosis is excluded, the remaining forms occur in approximately 1 in 70,000 individuals.<ref name="CTF">{{cite web |title=Schwannomatosis |url=https://www.ctf.org/swn/ |publisher=Children's Tumor Foundation |access-date=2026}}</ref>

Individuals with schwannomatosis develop schwannomas along nerves in the central nervous system (brain and spinal cord) and on peripheral nerves throughout the body. Although schwannomas are typically benign, they may cause neurological symptoms depending on their location, including pain, numbness, weakness, and hearing loss.<ref name="GeneReviews"/>