Endocrine Abstracts

Introduction: Ectopic Cushing’s syndrome (ECS) is a condition caused by an ACTH-secreting tumor outside the pituitary or adrenal glands. Most cases are caused by neuroendocrine tumors of the lung, pancreas, thymus or medullary carcinoma of the thyroid. Small-cell carcinomas of the lung are probably the most common cause of biochemical hypercortisolism. About 15% of Cushing’s syndrome cases are due to ECS.

Case description: A 27-year-old male patient presented to the clinic with a 4-months history of weakness, swelling, moon face, purple striae on the skin of the abdomen and thighs, hypertension, and hyperglycemia. On examination: BMI – 30.8 kg/m², T/A – 160/100 mmHg. Investigations: 0800 h Cortisol-474.0 ng/ml (64.1–209.4), ACTH-201 ng/l (12–62), FPG-168 mg/dl, HbA1c-4.6%, ALT-79(<41), electrolytes-N; 1600 h Cortisol-383.93 (30–160); urinary free Cortisol-153 μg/24 hours (3.5–45). After hypercortisolism was confirmed, further tests were done to determine the cause. MRI scans of the brain, abdomen and pelvic with no pathology. Next we performed MRI scan chest – 11×14 mm solid pulmonary nodule appeared in the left lower lobe. ECS was diagnosed. Diet, regimen and Metformin were recommended. Patient was referred to the thoracic surgeon.

Conclusion: The best treatment for ECS is surgical removal of the tumor. This is usually possible when the tumor is benign. However, many tumors are malignant, and have metastasized before cortisol excess has been diagnosed. Surgical removal is not possible in these situations, and drugs to suppress cortisol secretion may be given. Surgical removal of the tumor may lead to full recovery, but there is a chance of the tumor coming back. Survival for people with ectopic tumors depends upon the outcome associated with the particular tumor type.

References: 1. Ilias I, Torpy DJ, Pacak K, et al. Cushing’s syndrome due to ectopic corticotropin secretion: twenty years’ experience at the National Institutes of Health. J Clin Endocrinol Metab 2005; 90:4955. 2.Neary NM, Lopez-Chavez A, Abel BS, et al. Neuroendocrine ACTH-producing tumor of the thymus-experience with 12 patients over 25 years. J Clin Endocrinol Metab 2012; 97:2223. 3.Orth DN. Ectopic hormone production. In: Endocrinology and metabolism, 2nd, Felig P, Baxter JD, Broadus AE, Frohman LA (Eds), McGraw-Hill, New York 1987. p.1692.