schwannoma
Pronunciation: SHVAHN-oh-mah
Benign nerve sheath tumor arising from Schwann cells, most commonly affecting cranial and peripheral nerves.
Full Definition
Schwannoma is a benign peripheral nerve sheath tumor originating from Schwann cells that produce myelin around peripheral nerve axons. The most common intracranial location is the eighth cranial nerve (acoustic schwannoma or vestibular schwannoma). Histologically, these tumors show characteristic alternating Antoni A (compact, organized) and Antoni B (loose, myxoid) areas, with Verocay bodies being pathognomonic. Most schwannomas are sporadic, though bilateral acoustic schwannomas are associated with neurofibromatosis type 2. Complete surgical excision is typically curative due to their encapsulated nature.
Usage
Usage note: Specify anatomical location; distinguish from neurofibroma which lacks encapsulation.
In Context
- "The tumor showed classic Antoni A and B patterns with Verocay bodies, confirming the diagnosis of schwannoma." — Histopathology report
- "Bilateral acoustic schwannomas raised suspicion for NF2 syndrome." — Clinical correlation note