Ectopic pituitary adenoma of the clivus presenting with apoplexy: case report and review of the literature.

Ectopic pituitary adenomas usually occur within sphenoid sinus or nasopharynx, and seldom within the clivus. There is only a single reported example of ectopic adenoma with clinical apoplexy, albeit not from clivus. We report a 78-year-old male with known prostate carcinoma admitted with acute onset of blurred vision, suggestive of apoplexy. Work-up revealed unilateral cranial nerve VI palsy and neuroimaging showed a mass confined to the clivus; sellar region was normal. Preoperative considerations included chordoma, chondrosarcoma, or metastatic prostate carcinoma to bone. Resection was via endoscopic transsphenoidal approach to the clivus. An ectopic null cell pituitary adenoma with bland infarction was identified as the cause of the patient's clinical apoplexy. No antecedent precipitating factors for apoplexy were present; specifically the patient had not received leuprolide preoperatively, a known precipitant of pituitary apoplexy in prostate cancer patients who receive drug. We review the literature on ectopic clival pituitary adenomas, apoplexy in ectopic adenomas, and the link between apoplexy and leuprolide usage.