Schneiderian carcinoma developing in an inverted papilloma of the palatine tonsil: an unusual case.

Schneiderian papillomas are among the most common benign tumors of the nose and paranasal sinuses. These lesions frequently originate in the lateral nasal wall, and they have a tendency toward recurrence and malignant transformation. Carcinomas arise in association with schneiderian papillomas in approximately 10% of cases. Outside the sinonasal tract, the ectopic occurrence of a schneiderian papilloma is extremely rare. We describe the case of a 52-year-old man with an invasive schneiderian carcinoma that arose within an inverted papilloma in the palatine tonsil. To the best of our knowledge, no such case has been previously reported in the English-language literature.