Recurrent Primary Inverted Papilloma of the Mastoid with Intracranial Invasion: A 7-Year Follow-Up.

A 55-year-old man presented to the otolaryngology department complaining of aural fullness in his left ear after an episode of probable otitis 3 months before. magnetic resonance imaging revealed a soft tissue mass within the mastoid cavity that had destroyed the posterior wall of the middle ear with no apparent middle ear or sinonasal origin. The patient underwent a left canal wall-up tympanomastoidectomy, and the pathology report confirmed an inverted papilloma. Inverted papillomas are uncommon benign epithelial tumors related to a high recurrence rate and high risk of secondary malignant transformation after multiple surgeries. The patient has undergone 2 additional surgical interventions involving the neurosurgery team due to recurrent inverted papilloma that exerted a mass effect over the left cerebellar hemisphere. Despite no signs of recurrence on magnetic resonance imaging 5 years after the last surgery, at least 1 radiologic study per year is granted. Clinical multidisciplinary follow-up including nasal endoscopy and head and neck examination as a part of a stringent follow-up is essential to rule out synchronous nasosinusal inverted papillomas.