Cushing syndrome is a disorder that occurs when your body has a higher than normal level of the hormone cortisol. This hormone is made in the adrenal glands. Too much cortisol can be due to various problems. One such problem is a tumor on one of the adrenal glands. Adrenal tumors release cortisol.
Cancerous tumors that may cause Cushing syndrome include an adrenal carcinoma. This is a rare tumor, but it usually makes excess cortisol.
Nieman LK, Biller BM, Findling JW, et al. Treatment of Cushing's syndrome: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2015;100(8):2807-2831. PMID: 26222757 www.ncbi.nlm.nih.gov/pubmed/26222757.