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Updated: Aug 4, 2026

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Published on: September 15, 2017
Inappropriate ACTH concentrations in two patients with functioning adrenocortical carcinoma
Abstract:
Two female patients with functioning adrenocortical carcinomas had plasma ACTH detectable by RIA at presentation. In both patients there was evidence for biological activity of ACTH. There was no evidence for an ectopic source of ACTH, nor for a pituitary tumour. Urinary steroid analysis showed patterns of multiple hormone secretion characteristic of adrenocortical carcinomas. The finding of detectable ACTH concentrations in a patient with Cushing's syndrome does not exclude the presence of an adrenocortical tumour.
Insights
Detectable adrenocorticotropic hormone (ACTH) in patients with Cushing's syndrome can originate from adrenocortical tumors. This finding does not rule out adrenal cancer, even with evidence of ACTH biological activity.
Area of Science:
- Endocrinology
- Oncology
- Internal Medicine
Background:
- Cushing's syndrome is often caused by pituitary adenomas or ectopic ACTH production.
- Adrenocortical carcinomas can also cause Cushing's syndrome through hormone overproduction.
Observation:
- Two female patients with functioning adrenocortical carcinomas presented with detectable plasma ACTH levels via radioimmunoassay (RIA).
- Both patients exhibited evidence of biological ACTH activity.
- No ectopic ACTH source or pituitary tumor was identified in either case.
Findings:
- Urinary steroid analysis revealed patterns indicative of multiple hormone secretion, characteristic of adrenocortical carcinomas.
- Detectable ACTH concentrations were observed in the plasma of patients with adrenocortical carcinoma.
- The presence of biological ACTH activity was confirmed in these patients.
Implications:
- Detectable ACTH in Cushing's syndrome does not exclude an adrenocortical tumor diagnosis.
- This finding is critical for differential diagnosis in patients presenting with Cushing's syndrome.
- Further investigation into ACTH levels and sources is warranted in suspected adrenocortical carcinoma cases.
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Hypoglycemia and Glucagon
Cushing Syndrome I: Introduction
Cushing Syndrome II: Pathophysiology

