A report of 7 cases of adrenal tumors secreting both cortisol and aldosterone.

We report 7 cases of adrenal tumors with concurrent increases in cortisol and aldosterone secretion, which we have examined over the last 2 years. We also present the pathology of excised specimens based on immunohistochemical staining, as well as endocrinological findings. Four patients were male and 3 female; 6 were first diagnosed as suffering from primary aldosteronism (PA) and one as adrenal preclinical Cushing's syndrome (PCS). Plasma cortisol concentrations at midnight were greater than 2 microg/dl in 6 patients and more than 1 microg/dl in the dexamethasone suppression test with an 8 mg dose in all patients. This indicates that dexamethasone did not inhibit the secretion of cortisol. No increase in renin activity was seen in the renin-producing irritable test in any of the patients. Immunohistochemical staining showed not only the presence of aldosteronoma, but also the expression of P-450c17, which is involved in the biosynthesis of cortisol, indicating that both cortisol and aldosterone were concurrently synthesized. With regard to the function of adrenal tumors, we suggest that concurrent secretion of cortisol and aldosterone are not rare and that immunohistochemical examination of the surgically-extirpated specimen is important for diagnosis.