Clival prolactinoma masquerading as a chordoma: a case report.

Ectopic pituitary adenomas are a rare clinical entity and are frequently mistaken for other base of skull lesions on imaging. We report the clinical presentation and management of a woman presenting with an ectopic prolactinoma located in the clivus. A 66-year-old female presented with a 6-month history of headaches and light-headedness. Anatomical imaging demonstrated a clival lesion most suspicious for chordoma. Endocrinological assessment revealed modestly increased prolactin level with lower-than-expected gonadotrophins levels for her age. Surgical resection confirmed an ectopic prolactinoma. A skull base lesion in a patient with hormonal derangement should lend to a high clinical suspicion of an EPA as they may be treated with medications before surgery. Guidelines could assist clinicians investigating skull-based lesions to identify the rare, but important diagnosis of ectopic pituitary adenomas.