What are the surveillance recommendations following resection of sinonasal inverted papilloma?

BACKGROUND Inverted papilloma (IP) is a benign tumor of the nasal cavity and paranasal sinuses first described by Ward in 1854. IP is remarkable due to a high propensity for tumor recurrence with incomplete resection, potential for invasion of local structures, and an association with malignant transformation to squamous cell carcinoma. Surgery is the mainstay of treatment for sinonasal IP, and the initial controversy over the best approach for tumor removal has been replaced by the widespread use of endoscopic techniques when feasible. What remains unclear is the best practice for surveillance following surgery for a tumor that carries low but well-known potential for malignant transformation.