Inverted papilloma of frontal sinus with intracranial extension

Abstract

Inverted papilloma (IP) is a benign epithelial neoplasia that accounts for 0.5–4% of all primary nasal tumours.1 It is characterised by an endophytic or inverted growth pattern of epithelium with ramifications into the underlying stroma rather than outward proliferation from the surface with an intact epithelial basement membrane.2 It affects all ages, most commonly males (M:F 3:1–5:1) in the fifth to the seventh decades of life (average age 53 years).1,3 The most frequent sites are the lateral nasal wall near the middle turbinate or ethmoid recesses and the maxillary sinuses. Although a benign lesion, IP is characterised by its relatively high recurrence rate, local aggressiveness and potential for malignant transformation. We present a rare case of IP arising from frontal sinus with extension into anterior cranial fossa treated with craniofacial resection.