Spontaneous adrenocorticotropic hormone (ACTH) normalisation due to tumour regression induced by metyrapone in a patient with ectopic ACTH syndrome: case report and literature review

Background Ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS) is caused by tumours releasing ACTH. Ectopic ACTH-producing tumour regression is rarely induced using steroidogenesis inhibitors. We presented a case of EAS in which ACTH production by a lung tumour was reduced by metyrapone (MTP) and also reviewed previous cases of ectopic ACTH production suppressed via steroidogenesis inhibition.