Inverting papilloma (IP) is a benign tumor of the nasal cavity and paranasal sinuses that is best known for it’s invasiveness, and tendency to recur. More importantly, it is associated with malignancy, specifically squamous cell carcinoma, in approximately 10% of cases.
The exact etiology of inverting papillloma is largely unknown. While allergy has been linked to the development of these tumors, it has been discounted secondary to the lack of allergic history in many patients with inverting papilloma. Chronic rhinosinusitis has also been proposed as a possible etiologic factor. Additionally, there has not been any association found between inverting papilloma and environmental chemical exposure. Interestingly though, several studies have linked IP to the HPV virus.
The incidence of inverting papilloma has been documented as approximately 0.6 cases per 100,000 people per year. Common symptoms include unilateral nasal obstruction, epistaxis, nasal drainage, bilateral nasal obstruction, nasal mass, and sinusitis. Inverting papilloma affects males more commonly with a male to female ratio of 3:1. Cases are usually unilateral, with no side predilection. Inverting papilloma usually originates from the middle meatus or lateral nasal wall, involving at least one paranasal sinus 82% of the time: maxillary sinus (69%), ethmoid sinus (53-89%), sphenoid sinus (11-20%), and frontal sinus (11-16%).
Due to the propensity for invasiveness and its association with malignancy, surgical resection is usually the recommended treatment of choice. Traditionally, open/external surgical approaches have been used for tumor removal. Recently however, it has been noted that minimally invasive endoscopic resection (MIER) techniques have similar success rates.