Risks of malignancy in inverted papilloma of the nose and paranasal sinuses

PURPOSE OF REVIEW: The majority of inverted nasal papilloma are benign and treatment is by complete local surgical removal. There is an associated real, but small risk of malignancy, which may coexist at the time of presentation or develop at a later time. This article reviews some of the recent publications addressing the association of inverted papilloma with malignancy. RECENT FINDINGS: Neither the etiology of inverted papilloma nor the factors responsible for malignant transformation are fully elucidated to date. Inverted papilloma is associated with squamous cell carcinoma in approximately 10% of the cases. Malignancy may occur synchronously or metachronously. SUMMARY: Based on the literature, the rates of synchronous and metachronous carcinoma are 7.1 and 3.6%, respectively, although rates may be exaggerated due to a referral bias to tertiary centres. A thorough removal of all diseased mucosa is curative and a meticulous histological examination of the entire specimen is necessary. The working risk is approximately 10%. Recurrent disease and metachronous carcinoma can develop after a prolonged period of time. As most recurrences are due to incomplete resection, it is mandatory to perform a close follow-up, with biopsies performed when indicated. Life-long follow-up is recommended.