The use of ketoconazole in ectopic adrenocorticotropic hormone syndrome. The authors report a patient with ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS) resulting from small cell lung cancer. Treatment with ketoconazole (KCZ) resulted in significant suppression of serum cortisol levels. The authors confirmed KCZ to be a useful adjunct in the treatment of Cushing's syndrome. 