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Kaleb Yohay, MD
Amanda Bergner, MS, CGC
Section Editors
Helen V Firth, DM, FRCP, DCH
Jeremy M Shefner, MD, PhD
Patrick Y Wen, MD
Deputy Editor
April F Eichler, MD, MPH


Schwannomatosis is the third major form of neurofibromatosis, clinically and genetically distinct from neurofibromatosis type 1 (NF1) and neurofibromatosis type 2 (NF2), characterized by multiple noncutaneous schwannomas in the absence of bilateral vestibular schwannomas.

Patients typically present in adulthood with multiple schwannomas and pain, and approximately 20 percent of patients have a family history of schwannomas or schwannomatosis. Inactivating mutations in the tumor suppressor genes SMARCB1 and LZTR1 are thought to be responsible for a majority of cases. Treatment is symptomatic, focused primarily on pain management.  

The epidemiology, pathology, clinical manifestation, diagnosis, and treatment of schwannomatosis will be reviewed here. The following related topics are reviewed separately:

(See "Neurofibromatosis type 1 (NF1): Pathogenesis, clinical features, and diagnosis".)

(See "Neurofibromatosis type 2".)

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Literature review current through: Oct 2017. | This topic last updated: Aug 28, 2017.
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