Retrospective Case Series of Inflammatory Pseudotumor of the Skull Base

Background: Inflammatory pseudotumor (IPT) is a nonneoplastic fibroinflammatory lesion rarely found in the skull base. When occurring in this location, it is often extremely aggressive, resulting in bony destruction and cranial nerve palsy. The distinction between IPT and malignant process is impossible based on clinical history and radiology alone; therefore, tissue biopsy with culture is the only definitive diagnostic tool. Treatment of skull base IPT is controversial but involves immunosuppresion, radiotherapy, or surgery.

Methods: Retrospective case study.

Results: We treated five patients with IPT of the skull base. Presenting symptoms ranged from headache to acute hemiparesis with dysmetria. All patients presented with extensive skull base erosion, and two showed carotid artery dehiscence. Stealth-guided transnasal neuroendoscopy was used for definitive biopsy. All patients are currently treated with immunosuppressive therapy, including steroids, rituximab, or methotrexate, and are monitored with biannual MRI scans.

Conclusion: Skull base IPT often presents with vague symptoms, and diagnosis can be challenging. Stealth-guided biopsies are often necessary due to occult anatomic location. Aggressive initial treatment is advocated, including systemic steroid therapy, chemotherapy, radiotherapy, surgery, or a combination of these. Imaging plays an important role in assessing response to therapy.