Medullary Thyroid Carcinoma and Cushings’ Syndrome


I have a pt with mets. medullary CA of the thyroid. He is to undergo chemo per oncology, however, his potassium is low(2.2) and we suspect ectopic acth production. He is on IV potassium and Aldactone. 4AM cortisol in hospital was 46. ACTH and mid. sal. cort. is pending. Clinically, he is cushingoid with wt gain, full facies, hypertension, and low K. Will addition of ketoconazole help with the potassium? What dose? When should we see a response? When do we add metyrapone? What dose? Thank you for your help. J. Molinary,DO


Ketokonazole slowly increased up to 2g a day over two weeks can be beneficial. Follow plasma cortisol.If the pt cannot take per os iv etomidate can be a good altrenative.

Metyrapone can be added as a second drug if ketokonazole cannot block steroidogenesis.

George P. Chrousos, MD