Feminizing adrenocortical tumor: steroid hormone response to ketoconazole

A 58-yr-old man presented with gynecomastia and elevated serum estrogens. The diagnosis of an estrogen-secreting adrenal tumor was made based upon the finding of a 4-cm left adrenal mass, elevated levels of estradiol in peripheral and left adrenal venous blood, and increased urinary 17-ketosteroids. In addition to marked elevations in estradiol and 17-ketosteroids there was an increased baseline level of 11-deoxycorticosterone and a slightly decreased level of 18-hydroxycorticosterone, suggesting the possibility of impaired P450c11 activity. The effect of ketoconazole administration (600 mg/day) for 4 weeks was studied. Urinary free cortisol and 17-ketosteroid excretion and serum testosterone levels fell acutely (1 week). Serum estradiol levels decreased gradually over the 4-week course. Plasma aldosterone levels were essentially unaltered and 18-hydroxcorticosterone levels fell gradually, but there were marked increases in 11-deoxycorticosterone and corticosterone. Coincident with the increase in 11-deoxycorticosterone there was an increase in blood pressure and a transient fall in serum potassium. We conclude that ketoconazole administration may result in a hypermineralocorticoid state. Therefore, the usefulness of ketoconazole therapy for steroid hormone-producing neoplasms will depend upon the individual tumor's steroidogenic profile.