Clinical characteristics of sinonasal inverted papilloma associated with recurrence and malignant transformation

Sinonasal inverted papilloma is a benign tumor but has a potential for recurrence and malignant transformation. The aim of this article is to analyze the clinical characteristics of sinonasal inverted papilloma associated with recurrence and malignant transformation.A retrospective study was performed in all patients with sinonasal inverted papilloma diagnosed between in our hospital during May 2013 and May 2018.A total of 151 patients were enrolled in this study. The average age of these patients was 52.24 years, with a male-to-female ratio of 2.775:1, and the most frequent clinical symptom was nasal obstruction. The recurrence rate was 39.07% (59/151), the mean time of recurrence was 35.8 months and most recurrences occur within the first three years after surgery. There was no significant difference in recurrence rate between all four stages and between after endoscopic surgery and a combined endoscopic and external approach. The malignant transformation rate was 5.96% (9/151) and the mean time of malignant transformation was 9.06 months.Because of its high recurrence rate and the potential of malignant transformation, so it is important to determine the primary site of the tumor and to make a complete removal and a follow-up of at least five years after surgery is recommended.