[Invasive sinonasal papilloma with intracranial invasion: Case report and bibliographic review]

Inverted papilloma is a locally-aggressive benign neoplasm of the paranasal sinuses with a high potential for recurrence and malignancy. Intracranial extension is infrequent, and dural penetration even more so, typically associated with recurrence of the disease or its degeneration into squamous cell carcinoma.

A 32-year-old female patient consulted us for an exophytic lesion in her right nostril and exophthalmos, associated with headache, anosmia and dysgeusia. Craniofacial and brain CT and brain MRI demonstrated a lesion in the right nostril, extending into the aerial sinuses, orbital lateral wall and anterior fossa, with osteolysis and intracranial invasion towards the right frontal region. A mass effect and brain compression were noted. A histological diagnosis of inverted papilloma was made initially. Upon later resection of the lesion by double access, with reconstruction of the anterior cranial fossa, a definitive diagnosis was made of inverted papilloma of the Schneiderian type, with areas of atypical transformation in situ. Post-operatively, the patient has had a favorable course, with full upper airway patency and neither complications nor signs of recurrence after four years of follow-up.

Intracranial invasion of this pathology is extremely uncommon. When it exists, the tumor has a high potential for local recurrence. Consequently, complete excision of the lesion determines the patient's prognosis.