Fine-needle aspiration cytology of sclerosing perineurioma.

Sclerosing perineurioma is a recently described rare benign nerve sheath tumor. The cytopathology of this neoplasm has, to our knowledge, not previously been described. We report the fine needle aspiration cytopathology of sclerosing perineurioma, discuss potential pitfalls in cytologic interpretation, and compare the aspirate with the corresponding resection specimen.