Inverted papilloma: a single institution experience with 91 cases

Objectives: Inverted papilloma is a benign tumor associated with local aggressiveness, high rates of recurrence, and possible malignant transformation. The probability of malignant transformation and recurrence rates are difficult to estimate because of the highly variable rates described in studies. The aims of our study were to show the risk of malignant transformation and recurrence in 91 cases treated at our institution from 1992 to 2012; determine if synchronous or metachronous malignancy is more likely to occur; and evaluate whether gender and age are risk factors for malignant transformation or recurrence of inverted papilloma. Methods: Ninety-one patients with histologically confirmed inverted papilloma were included. Data regarding gender, age, malignant transformation, and recurrence within at least five years from initial diagnosis were collected. Results: There were 66 men and 25 women. The recurrence rate was 18.7% and malignancy occurred in 13% of patients. Only one malignancy was found metachronous to inverted papilloma. There was no significant difference regarding patients’ age and sex and malignant transformation or recurrence. Conclusion: Inverted papilloma is a benign disease with a risk of malignant transformation and recurrent disease. Synchronous malignancies were more frequent and, according to our results, the risk of developing malignancy after an initial benign finding is low.