Ketoconazole. Use in the treatment of ectopic adrenocorticotropic hormone production and Cushing's syndrome in small-cell lung cancer.

Recently, ketoconazole, an imidazole derivative with antifungal properties, has been shown to inhibit adrenal corticosteroid and androgen production. We treated a patient with small-cell lung cancer and Cushing's syndrome secondary to ectopic secretion of adrenocorticotropic hormone in whom it was necessary to discontinue chemotherapy. The patient was treated with ketoconazole, with a resultant reduction in urinary free cortisol and ketosteroid excretion and improvement in electrolyte balance. Ketoconazole may be a useful adjunct in the treatment of small-cell lung cancer or other malignancies associated with excessive corticosteroid production or as a hormonal therapy in breast or prostatic cancer.