<prompt> The most common cause of Cushing;s syndrome is-Pituitary adenomaAdrenal adenomaEctopic ACTHIatrogenic steroids  <response>: mc cause of ACTH dependent cushings syndrome is PITUTATRY ADENOMA. MC cause of ACTH independent cushings syndrome is IATROGENIC STEROIDS. OVER ALL MC cause of cushings syndrome is IATROGENIC STEROIDS. Reference : page 2314 Harrison;s Principles of Internal Medicine 19th edition 