Endoscopic endonasal biopsy for a tumor at the cavernous sinus and pons.

Lesions at the cavernous sinus and brainstem can be detected by radiologic studies, but a definitive diagnosis depends on histopathologic analysis. We present the case of a 75-year-old woman with symptoms including cranial nerve palsy, hydrocephalus,seizures, and long-term coma caused by squamous cell carcinoma at the cavernous sinus and ventral pons, which was confirmed by an endoscopic endonasal biopsy.