[Evaluation of various parameters in the differential diagnosis of Cushing's disease and Cushing's syndrome caused by adrenal adenoma].

Evaluation of the clinical and biochemical parameters for differential diagnosis of two types of Cushing's syndrome, pituitary-dependent Cushing's disease and adrenal adenoma, was studied with analysis of the histories of 79 cases of Cushing's disease and 23 cases of adrenal adenoma. The data show that the symptoms, signs and the routine biochemical analyses were not significantly different between two groups. High-dose dexamethasone suppression test had about 90% coincidence rate in the differential diagnosis with 24-hour urine free cortisol (UFC), which was better than 24-hour urine 17-OHCS. Interestingly, low-dose dexamethasone test was highly valuable and the 24-hour urine 17-KS quite helpful in the differential diagnosis of two types of Cushing's syndrome. Serum N-POMC measurement was the most valuable among the parameters, because there was no overlap between the two groups of Cushing's syndrome.