Intracranial inverting papilloma.

BACKGROUND

Inverting papillomas usually originate from the lateral wall of the nose and sporadically from the ethmoid, maxillary, sphenoid, or frontal sinuses. Intracranial extension and dural penetration is rare and often associated with recurrent disease that has degenerated into squamous cell carcinoma. A case of inverting papilloma with dural penetration in the absence of malignant degeneration has prompted an investigation into the incidence and treatment of dural invasion by benign inverting papilloma.

METHODS

A literature search revealed 1468 cases of inverting papilloma. A detailed analysis was performed to obtain data on the incidence of intracranial invasion.

RESULTS

Of the 1468 cases, 5 were noted to be associated with intracranial extension without histologic evidence of malignancy (0.34%). Treatment consisted of surgery alone in 3, radiotherapy in 1, and combined therapy in the last patient. Dural invasion was documented histopathologically in one case.

CONCLUSION

Intracranial extension and dural penetration of benign inverting papilloma is extremely rare, and a uniform treatment plan has not been established. Further investigation is necessary in the pathophysiology and management of intracranial inverting papilloma.