Frontal Sinus Inverted Papilloma: Surgical Challenges and Outcomes of a Multi‐Institutional Cohort

Objectives Inverted papilloma (IP) is typically a benign sinonasal tumor with a propensity to recur. The surgical treatment of IP arising from the frontal sinus is complicated by proximity to the orbit and skull base. The objective of this study is to describe the surgical challenges when managing this disease and report treatment outcomes in a multicenter cohort. Methods A retrospective review was performed on frontal sinus IP resected from 1993 to 2023. Demographic and clinicopathologic data, complications, surgical approach, and outcomes were analyzed. Results Ninety‐eight patients (60 males, 38 females) were identified. Mean age was 59 years, with a median follow‐up of 44 months. Histopathologic evaluation identified 13 lesions with carcinoma in situ or invasive carcinoma (13.3%). Bilateral involvement was found in 28 patients (28.6%). Overall, 17 patients (17.3%) had recurrent disease with a median recurrence time of 29.2 months. Fourteen patients (14.3%) underwent staged procedures, with a median time to the second procedure of 7.7 months. Twenty‐three patients (23.5%) presented with skull base dehiscence on perioperative imaging. Skull base dehiscence had a significant effect on intraoperative cerebrospinal fluid leak (OR 9.1, 95% CI 3.0–27.4 p < 0.001). Conclusion Frontal sinus IP is commonly attached at the skull base and associated with skull base dehiscence, CSF leak, and often requires operative repair and staged procedures. Complete tumor removal can be challenging and may necessitate a combined open and endoscopic approach. Careful surgical planning and close follow‐up in the postoperative period are essential for disease control. Level of Evidence Level 4.