Need for long-term follow-up in sinonasal inverted papilloma: A Single-institution experience.

BACKGROUND Most studies on sinonasal inverted papillomas (SNIPs) regarding risk factors for recurrence, recurrence rates (RRs) and malignant transformation are biased by a significant proportion of revision cases. METHODS Retrospective study on patients with consecutive, treatment-naive SNIPs at a tertiary referral center between 1999 and 2019. RESULTS Overall, RR was 9.8% (10 of 102 patients), with 2 of 10 recurrences (20%) occurring after more than 5 years. Histopathological workup revealed synchronous malignancy in 2 of 102 patients (2%). Subgroup analysis revealed a significantly higher RR for SNIPs involving the frontal sinus (26.3% vs 6.0%, P = .02). No SNIPs primarily originating from the frontal sinus were observed. CONCLUSION Overall, RR of treatment-naive SNIPs is comparably low; however, long-term follow-up is mandatory due to late recurrences. Secondary involvement of the frontal sinus was identified as risk factor for recurrence. No SNIPs primarily originating from frontal sinus were observed.