Schwannoma

Schwannoma
File:Schwannoma - Antoni A and B - very high mag.jpg Micrograph of a schwannoma showing both a cellular Antoni A area (center and right of image) and a loose paucicellular Antoni B area (left edge of image). HPS stain.
Classification and external resources
Specialty
ICD-10	C72.4
ICD-9-CM	225.1
ICD-O	M9560/0
DiseasesDB	33713
Patient UK	Schwannoma
MeSH	D009442

A schwannoma (also known as an "neurilemoma," "neuroma," "neurolemoma," and "Schwann cell tumor") is a benign nerve sheath tumor composed of Schwann cells, which normally produce the insulating myelin sheath covering peripheral nerves.

Schwannomas are homogeneous tumors, consisting only of Schwann cells. The tumor cells always stay on the outside of the nerve, but the tumor itself may either push the nerve aside and/or up against a bony structure (thereby possibly causing damage). Schwannomas are relatively slow-growing. For reasons not yet understood, schwannomas are mostly benign and less than 1% become malignant, degenerating into a form of cancer known as neurofibrosarcoma.

Schwannomas can arise from a genetic disorder called neurofibromatosis. They are universally S-100 positive.

Schwannomas can be removed surgically. Recurrences after total removal are rare.

Verocay bodies are seen histologically in schwannomas.

See also

• Intranodal palisaded myofibroblastoma
• List of inclusion bodies that aid in diagnosis of cutaneous conditions

Additional images

• Schwannoma - Antoni A and B - intermed mag.jpg
• Peripheral schwannoma Antoni type A (2).JPG
• Subcutaneous schwannoma (1) Antoni B.jpg

  Subcutaneous schwannoma

• Subcutaneous schwannoma (2) Antoni B.jpg
• Subcutaneous schwannoma (3) Antoni B.jpg
• Subcutaneous schwannoma (4) S-100 immunostain.jpg

See also

• Neurofibroma
• Vestibular schwannoma (Acoustic neuroma)