Question: Is there any kind of a thyroid tumor or nodule that can cause Cushing’s?

Answer: Almost all of cases of Cushing’s syndrome are caused by a pituitary tumor or adrenal growth. It is uncommon to have Cushing’s syndrome due to another type of tumor, called “ectopic”, and, of the ectopic types, thyroid tumors are rare. There have been reports of a type of thyroid cancer, called medullary thyroid cancer, causing Cushing’s syndrome by producing high amounts of ACTH, the hormone that causes the adrenal glands to produce steroids.

By Dr. Laurence Katznelson MD (Spring, 2007)