Schwannomatosis

Schwannomatosis
Micrograph of a schwannoma
Specialty	Oncology

Schwannomatosis is an extremely rare genetic disorder closely related to the more-common disorder neurofibromatosis (NF). Originally described in Japanese patients,^[1] it consists of multiple cutaneous schwannomas, central nervous system tumors, and other neurological complications, excluding hallmark signs of NF. The exact frequency of schwannomatosis cases is unknown, although some populations have noted frequencies as few as 1 case per 1.7 million people.^[2]

Schwannomas are mostly benign tumors that commonly occur in individuals with NF2 and schwannomatosis (sometimes called neurofibromatosis type III). Schwann cells are glial cells that myelinate the axons of nerve cells. Myelin is a lipid covering that speeds the conduction of action potentials. When Schwann cells proliferate out of control in an encapsulation it is called a schwannoma. Although schwannomas are benign they become detrimental when the growing tumor compresses the nerve. Schwannomas on sensory nerve axons cause chronic severe pain. Treatment options for schwannomas are to surgically remove them, have radiation, cyberknife or intracapsular enucleation. Previous designations for schwannomas include neurinoma and neurilemmoma.^[3]