Related Experiment Video
Updated: Jun 5, 2026

Endoscopic Endonasal Trans-sphenoidal Approach: Minimally Invasive Surgery for Pituitary Adenomas
Published on: January 17, 2018
Unusual double pituitary adenoma: a case report
Fabio Rotondo1, Nasima Khatun, Bernd W Scheithauer
1Department of Laboratory Medicine, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada. rotondof@smh.ca
Abstract:
We report the case of a 60-year-old woman with Cushing disease. Magnetic resonance imaging (MRI) revealed a large sellar and suprasellar mass involving the right cavernous sinus, consistent with pituitary macroadenoma. It was resected by transsphenoidal surgery. Light microscopy revealed two separate pituitary adenomas with different histologic and immunohistochemical features. One was amphophilic and strongly Periodic Acid-Schiff (PAS) positive, the other chromophobic and PAS negative. The former tumor was immunopositive for adrenocorticotropic hormone (ACTH); approximately 30% tumor cells were immunopositive for MGMT (O6-Methylguanine-DNA Methyl-Transferase). The second tumor was a PAS negative, luteinizing hormone (LH) and alpha subunit immunopositive gonadotroph adenoma. In this tumor, about 90% of the cells were immunopositive for MGMT. The Ki-67 nuclear indices of the two tumors were 6% and 2%. Our case represents a rare combination of two morphologically different pituitary adenomas, one producing ACTH and the other LH and alpha subunit. The two tumors differed not only in Ki-67 labeling indices but in MGMT immunoexpression as well.
Related Concept Videos
Cushing Syndrome II: Pathophysiology
Cushing Syndrome I: Introduction
The Pituitary Gland
Adrenal Gland Disorders
Adrenal insufficiency, characterized by insufficient cortisol and aldosterone production, leads to conditions like Addison's disease. This disorder, affecting the adrenal cortex, exhibits symptoms such as skin bronzing, dehydration, low blood pressure, fatigue, and weight loss. Congenital adrenal hyperplasia, a genetic ailment causing...