Inflammatory pseudotumors of the skull base.

Inflammatory pseudotumor is a rare affliction of the skull base with a propensity for locally aggressive growth. Frequently, the location of involvement does not lend itself to conventional biopsy techniques, resulting in diagnostic and treatment dilemma. A retrospective review of three unusual cases of skull base inflammatory pseudotumors is reported. These lesions illustrate the difficulty of management by virtue of their histopathology and behavior. They are clinically and radiographically indistinguishable from invasive neoplasms. One involved the petrous apex with bony erosion; a second case presented with pain and trigeminal paresthesia secondary to an infiltrative lesion in the clivus and the sphenoid sinus; and the third case involved peritubal soft tissues of the infratemporal fossa, with mandibular paresthesia and middle ear effusion. All three lesions were resected via lateral skull base approaches with no evidence of recurrence. Because of the inherent nature of this lesion and its rarity, inflammatory pseudotumor should remain a diagnosis of exclusion. When suspected, surgical approaches should be designed to allow complete extirpation with limited morbidity.