In approximately 80% of cases, CS is a consequence of an adrenocorticotrophin (ACTH) hypersecretion (ACTH-dependent CS), generally due to an ACTH-secreting pituitary tumor (pituitary-dependent CS or Cushing’s disease [CD], 70%), and, rarely, to an ACTH-secreting, or corticotrophin-releasing hormone-secreting, extra-pituitary tumor (ectopic CS, 10%) [3]. The gene discussed is POMC; the disease is Cowden disease.