Ectopic Pituitary Adenoma within the Sphenoid Sinus

A 69-year-old woman presented with right abducent nerve paresis caused by an ectopic pituitary adenoma invading the posterior wall of the sphenoid sinus. The tumor was removed via transsphenoidal approach. The histological diagnosis was invasive pituitary adenoma with bony destruction. The symptom was improved without complication. The authors present a rare case of ectopic pituitary adenoma with a literature review.