43-year-old female had a painful subcutaneous tumor (surgical resection specimen).
- Circumscribed tumor consisting of spindle cells with fusiform nuclei.
- In some areas closely packed cells growing in a fasciculated or whorled pattern (Antoni A pattern). Some nuclei form orderly palisades (Verrocay bodies).
- In other areas loosely packed, haphazardly arranged elongated cells in a myxoid stroma (Antoni B pattern).
- Between tumor cells fine fibers arranged in parallel are observed.
- Some vessels show a hyalinized wall and the stroma is focally hyalinized (so called ancient change)
Bilateral vestibular schwannomas are commonly found in patients with neurofibromatosis Type 2. In addition, these patients develop schwannomas of other cranial and peripheral nerves and have a predisposition to develop meningeomas and gliomas.
Tumors are diffusely positive for S-100.