title: Endoscopic Endonasal Surgery for Remission of Cushing Disease Caused by Ectopic Intracavernous Macroadenoma: Case Report and Literature Review.
abstract: BACKGROUND
  Complete surgical resection of an adrenocorticotropic hormone (ACTH)-secreting pituitary adenoma is the gold standard of treatment of Cushing disease. Ectopic location of these adenomas is an extremely rare condition that may compromise the diagnosis and surgical success. We present the first case of an ectopic intracavernous ACTH-secreting macroadenoma totally resected with endoscopic endonasal surgery (EES).
  
  
  METHODS
  A 36-year-old woman presented with Cushing syndrome. Increased ACTH, serum cortisol, and free urine cortisol levels were identified; however, pituitary magnetic resonance imaging failed to show a pituitary tumor; instead, a parasellar lesion in the left cavernous sinus (CS) was noticed. Inferior petrosal sinus sampling showed a significant central to peripheral and lateralized left-sided ACTH gradient. The patient underwent EES. No tumor was found in the sella; however, the left CS was widely explored and a tumor was found lateral to the paraclival segment of the carotid artery. There were no complications after EES. Pathology confirmed the diagnosis of an ACTH-secreting adenoma. During the immediate postoperative course, serum cortisol levels decreased lower than 5 μg/dL. Postoperative magnetic resonance imaging showed complete tumor resection. At 20 months follow-up, the patient remained in clinical and biochemical remission of Cushing disease.
  
  
  CONCLUSIONS
  Only 12 cases of ectopic intracavernous ACTH-secreting adenomas have been reported and all were microadenomas. The presence of an ectopic ACTH-secreting macroadenoma in the CS represents a surgical challenge. EES is the ideal approach for complete resection of ectopic intracavernous adenomas, allowing for a wide exploration of the CS with no surgical complications.
authors.affiliation: Department of Neurological Surgery, University of Louisville, Louisville, Kentucky, USA. Electronic address: maria.koutourousiou@louisville.edu.
authors.forename: Maria
authors.initials: M
authors.lastname: Koutourousiou
authors.affiliation: Department of Otolaryngology, University of Louisville, Louisville, Kentucky, USA.
authors.forename: Welby I
authors.initials: WI
authors.lastname: Winstead
mesh_terms: D049913:ACTH-Secreting Pituitary Adenoma / Q000150:complications* / Q000601:surgery; D000236:Adenoma / Q000150:complications* / Q000601:surgery; D000328:Adult; D003480:Cushing Syndrome / Q000209:etiology / Q000601:surgery*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D057605:Natural Orifice Endoscopic Surgery / Q000379:methods*; D019635:Neurosurgical Procedures / Q000379:methods*; D012074:Remission Induction
keywords: ACTH-secreting pituitary adenoma; Cushing disease; Ectopic pituitary adenoma; Endoscopic endonasal surgery; Transsphenoidal surgery