Incidence of inverted papilloma in recurrent nasal polyposis.

Objectives: A diagnosis of inverted papilloma in apparently normal bilateral polyps is a possible albeit rare event. The frequency of this diagnosis varies between 0.00% and 0.92%. There are no studies evaluating whether this possibility is significantly different in patients operated for recurrence when compared with those undergoing first surgery. The aim of this study is to evaluate the frequency of inverted papilloma in a series of histologic specimens obtained from patients undergoing surgery for recurrent nasal polyposis.
Methods: The authors conducted a retrospective chart and pathologic review of data from 1887 surgical interventions for removal of unremarkable bilateral nasal polyps. Frequency of inverted papilloma was assessed.
Results: Five cases of inverted papilloma were identified. The incidence of this diagnosis was thus 0.26% (95% confidence interval, 0.08-0.62%). Age, gender, and number of recurrences did not influence the frequency of this diagnosis.
Conclusions: The occurrence of inverted papilloma in unremarkable recurrent cases of nasal polyps is rare. This rate is similar to the one observed in patients undergoing first surgery.