CUSHINGS-SYNDROME - APROPOS OF A NATIONAL SERIES

Gushing's syndrome occurs rarely; in analyzing 50 cases studied at our institution we discuss the following aspects: syndromatic diagnosis, etiologic differentiation into the 3 categories of the syndrome and th erapeutic strategies for each variety. We postulate that non-endocrino logists should be responsible for the syndromatic diagnosis, easily do ne by using 2 simple tools: the measurement of basal free urinary cort isol and the performance of an overnight suppression of the adrenal ax is with I mg of dexamethasone (Nugent's test). In contrast the etiolog ic diagnosis and the therapeutic interventions should be strictly rest ricted to highly specialized institutions having well seasoned endocri nologists, a reliable endocrine laboratory, easy access to computed to mographies of the brain and abdomen as well as to nuclear resonance im aging of the brain. The usefulness of our in-house devised vasopressin challenge following overnight dexamethasone suppression for the etiol ogic diagnosis is highlighted. Neurosurgical expertise in the transsph enoidal approach to the pituitary gland as well surgeons well experien ced in adrenal surgery are a must to offer a reasonable chance of succ ess to patients with the syndrome. Forty one (82%) of the series were female patients, 78% were pituitary-dependent and 22% pituitary-indepe ndent Cushings. Six out of 8 (75%) of the adrenal tumors were carcinom as. Only 3 patients (6%) qualified as ectopic ACTH syndromes. The easi est variety to diagnose and treat was the adrenal adenoma (2 cases); a drenal carcinomas were always incurable. The ectopic ACTH syndrome was amenable to successful medical treatment with ketoconazole or surgica l resolution with complete resection of the offending tumor (1 of 3 ca ses) or bilateral adrenalectomy (2 of 3 cases) Pituitary-dependent Cus hings are quite tricky to diagnose and difficult to treat. Transspheno idal resection of the offending microadenoma was successful in only 43 ,5% (10/23) of cases and we experienced 3 recurrences of the syndrome even after 8 years of successful removal of the pituitary adenoma. The remainder had to be cured by bilateral adrenalectomy. Seven out of 39 patients with Gushing's disease (18%) ultimately died for a variety o f reasons; six out of 6 patients (100%) with adrenal carcinoma died of dissemination; two out of 2 adrenal adenomas cured and 1 out of the 3 ectopic ACTH syndromes died of dissemination of a malignant thymic ca rcinoma. We conclude that Gushing's syndrome is a serious, underdiagno sed disorder, which should be suspected and diagnosed by the non speci alized physician and then referred to a specialized center for expert etiologic diagnosis and surgical therapy.