[Inverted papilloma of the nose and paranasal sinuses. Retrospective study of 18 cases].

The authors report about 18 cases of inverted papillomas treated between 1981 and 1991. The average age of the patients is 51 years, with a marked male predominance. The average follow-up is of 4 years. The most often noted revealing sign is unilateral nasal obstruction. A history of polypectomy and nasosinual surgery is found in 45% of the cases in our series. The treatment was surgical in all cases, including 4 De Lima's procedures, 11 procedures through a paralateronasal approach, 2 ethmoidectomies through an endonasal approach, and 1 degloving for a septal lesion. Endonasal surgery was performed for two limited tumors, for which the diagnosis of inverted papilloma never could be made preoperatively. The recurrence rate observed in our series is 5%. Out of 18 patients, 4 presented with a malignant change, either at once (2 cases) or some time after the primary exeresis of the inverted papilloma (2 cases). In the light of the results, and after analyzing the literature, the authors reassert the necessity of radical exeresis for inverted papilloma. Rhinosinual endoscopy must remain a diagnostic means and never is an indication of exeresis of inverted papilloma. The authors emphasize the difficulty of the histological diagnosis and set forth the various problems arising from the malignant degeneration of inverted papillomas. Recent discoveries on viral etiopathogenesis and on the oncogenic potential of the type-16 papilloma virus may allow characterizing the evolutive and prognostic features of inverted papillomas in the future.