Schwannomatosis is a rare autosomal dominant disorder characterized by multiple benign tumors that originate from schwann cells. Schwann cells cover the nerves in the peripheral nervous system. Schwannomatosis is a benign homogenous tumor and it consists of only schwann cells. The primary symptom of schwannomatosis is pain in the affected areas, which can be in any part of the body, but it most commonly occurs near the bases of the skull, spine, arms, or legs. In about one-third of the affected patients, schwannomas are restricted to a particular area in the body. As the tumor develops, the pain worsens due to increasing nerve compression. Rarely, the patients affected with schwannomatosis have associated neurologic symptoms including memory loss, vision problems, and weakness.
Mostly, the cases are of ages between 20 and 40 years, however, schwannomatosis can occur in any age. Males and females are equally affected, and the prevalence is estimated to be 1:2,000,000 individuals. Tumors are detected via X-ray, CT scan, or MRI to establish the diagnosis of Schwannomatosis. Pain medications and surgery is efficient for those patients which enable them to live a healthy life.
Schwannomatosis exhibits an autosomal dominant transmission, however, some cases are found to be sporadic. Most of the patients have shown somatic mutations in a tumor suppressor gene known as neurofibromin-2 (NF2) gene. NF2 gene encodes a cytoplasmic peripheral protein (schwannomin) which interacts with cytoskeleton proteins; therefore, it is important for cellular adhesion. This gene is mapped to the locus 22q12.2. Mutations in SMARCB1 (SWI/SNF Related, Matrix Associated, Actin Dependent Regulator of Chromatin, Subfamily B, Member 1) gene is known to confer susceptibility to the development of schwannomatosis 1.