corticotroph adenoma
A pituitary tumor secreting excess ACTH, causing Cushing's disease through chronic hypercortisolism.
Full Definition
A corticotroph adenoma is a benign pituitary tumor arising from ACTH-secreting corticotroph cells in the anterior pituitary, representing the most common cause of Cushing's disease. These adenomas autonomously secrete adrenocorticotropic hormone, leading to bilateral adrenal hyperplasia and excessive cortisol production. Most corticotroph adenomas are microadenomas (<10mm) at presentation, making them challenging to visualize on routine MRI studies. The resulting hypercortisolism causes characteristic clinical features including central obesity, purple striae, muscle weakness, diabetes, and psychiatric symptoms. Diagnosis relies on demonstrating inappropriate ACTH secretion through dexamethasone suppression tests and corticotropin-releasing hormone stimulation, with treatment typically involving transsphenoidal surgery followed by adjuvant therapy if remission is not achieved.
Usage
Usage note: Distinguish from other pituitary adenoma subtypes; specify functional vs. non-functional when relevant to clinical presentation.
In Context
- "MRI revealed a 6mm corticotroph adenoma in the right anterolateral pituitary gland." — Radiology report
- "Immunohistochemistry confirmed strong ACTH positivity within the resected corticotroph adenoma." — Surgical pathology report