Cytomorphologic findings of Schneiderian papilloma: a case report.

Schneiderian papilloma or inverted papilloma (IP) is the most common sinonasal papilloma yet a rare tumor with the greatest potential for recurrence and local destruction and association with malignant transformation. Tissue biopsy is routinely performed to examine these lesions. However, Fine needle aspiration may provide an immediate diagnosis. Herein, we report cytomorphologic findings of IP in a 46-year-old man with histopathologic correlation and review of the literature.