In this study, 55 patients with
Cushing's syndrome (CS) (50 female, 5 male; mean age 34 +/- 12.3 yr) who attended our clinics between the years 1983 and 2000 were retrospectively evaluated for clinical and laboratory features and modalities and results of
therapy, due to a few similar studies over the last ten years.
Cushing's disease was diagnosed in 39 patients (71%), adrenal
adenoma in 13 patients (23.6%) and adrenal
carcinoma in 3 patients (5.5%). Centripedal
obesity, moon face,
hypertension,
hirsutism and purplish stria were the most frequent findings. Loss of normal serum F circadian rhythm was found in all patients with CS. The overnight 1 mg oral
dexamethasone suppression test and low-dose
dexamethasone suppression test (LDDST) yielded 100% and 100% diagnostic sensitivity for CS, respectively. Sensitivity and specivity of the high-dose
dexamethasone suppression test (HDDST) in distinguishing
Cushing's disease was found to be 82% and 100%, respectively. All of the patients with adrenal CS were not suppressed with HDDST. Sellar CT and/or MRI accurately identified the
tumor in 58% of these patients. Recurrence was observed in 3 (11%) of the 28 patients with
Cushing's disease, treated by transsphenoidal adenomectomy. Recurrence was diagnosed 1.5, 3 and 6 yr after the operation in these 3 patients. One patient had residue
tumor. In our case series, bilateral
adrenalectomy plus
pituitary irradiation achieved the highest remission rate (100%) in
Cushing's disease. In 2 out of 4 patients (50%) treated by left
adrenalectomy associated with
pituitary irradiation, recurrence was observed.
Panhypopituitarism due to
tumor apoplexy was observed in one of the patients with
Cushing's disease. All of the patients with adrenal CS, the
tumor was accurately localized with imaging methods before the operation. The appropriate operative procedure resulted
in complete remission in patients with adrenal
adenoma. Consequently,
Cushing's disease was the most common form of CS. The overnight 1 mg oral DST and 24-h urine free F excretion (UFC) as screening tests, 2-day LDDST as diagnostic test and 2-day HDDST as differential diagnostic test were good studies. More successful outcomes have been achieved in treatment of
Cushing's disease with the development of pituitary surgery in the recent years, as well as in our case series. Surgery is also curative for adrenal
adenoma patients. Survival remains poor among
carcinoma patients.