The former is, in turn, due to the presence of ACTH-secreting pituitary adenomas (Cushing’s disease) in 75-80% of cases; an ectopic production of ACTH (pulmonary microcarcinoma, neuroendocrine tumors, etc.)is present 15-20% of the cases, and CRH-dependent forms have a prevalence of <1%. Here, POMC is linked to pituitary gland adenoma.