POMC and ACTH-producing pituitary gland adenoma: Among ACTH-dependent CS cases, 80–90% arise from corticotroph pituitary adenomas (Cushing’s disease or corticotropinoma), representing approximately 65% of all CS cases, while the remaining 10–20% result from ectopic ACTH-secreting tumors (Ma et al. 2016; Gadelha et al. 2023).