Peripheral primitive neuroectodermal tumor of the parotid gland region: report of a case with fine-needle aspiration findings.

A case of peripheral primitive neuroectodermal tumor of the parotid gland region in a 38-yr-old woman is reported. She had a 1-yr history of a large, firm, and slightly tender left parotid-region mass. CT scan showed an invasive tumor involving the parotid gland, mandible, infratemporal fossa, and parapharyngeal space. Fine-needle aspiration cytology of the mass showed a highly cellular, poorly cohesive smear pattern exhibiting small cuboidal cells, with fibrillary cytoplasm forming occasional rosette-like structures. Numerous intact single cells with fragile cytoplasm, finely granular chromatin, and inconspicuous nucleoli were present together with free-lying nuclei in the background. Histologic, immunohistochemical, and ultrastructural findings confirmed the diagnosis. Diagn. Cytopathol. 2000;22:161-166. Published 2000 Wiley-Liss, Inc.