Inverted Papilloma

Centered in the left nasal cavity there is T1 hypointense, STIR hypointense, heterogeneously enhancing mass which laterally bows the medial wall of the left maxillary sinus, obstructs the left ostiomeatal complex, erodes through the left middle and inferior turbinates, and demonstrates restricted diffusion compatible with hypercellularity. There are post-obstructive secretions in the left maxillary, frontal, and sphenoid sinuses. The internal architecture of the mass shows curvilinear striations which appear cerebriform or convoluted. The location and imaging features are characteristic of an inverted papilloma. Ten percent may degenerate or coexist with squamous cell carcinoma with necrosis or invasion being an indicative imaging feature. Treatment entails surgical resection. If incompletely resected, they have a high recurrence rate.