Hormonal activity in clinically silent adrenal incidentalomas

INTRODUCTION: The rapid development of modern imaging techniques, has led to an increase in accidentally discovered adrenal masses without clinically apparent hormonal abnormalities. Such tumours have been termed “incidentalomas”. The diagnostic work-up in patients with adrenal incidentalomas is aimed at the determination of hormonal activity of the tumour and identification of patients with potentially malignant tumours. The aim of our study was a retrospective analysis of selected clinical characteristics and hormonal studies in accidentally discovered adrenal tumours. MATERIAL AND METHODS: Fourty hundred sixty-three patients with serendipitously discovered adrenal masses, diagnosed and treated in the Department of Endocrinology and Internal Diseases, Medical University of Gdansk as well as in the affiliated Endocrinology Clinic between 1993 and October of 2009 were included in the analysis. Out of all patients, 245 were referred for adrenalectomy. RESULTS: We found that clinically “silent” tumours often demonstrate subclinical hormonal activity. In our report, increased 24-h urinary excretion of cortisol correlated positively with tumour size (p < 0.001). Moreover, a statistical relationship was demonstrated between tumour size and serum cortisol concentration assessed in the 1 mg dexamethasone suppression test (p < 0.001). Increased values of dehydroepiandrosterone/dehydroepiandrosterone sulphate were more often found in malignant than in benign tumours (p < 0.01). Urinary concentrations of 17-ketosteroids correlate positively with diagnosis of adrenocortical cancer (p = 0.02). CONCLUSIONS: We found that clinically “silent” tumours often demonstrate subclinical hormonal activity (subclinical Cushing syndrome, subclinical pheochromocytoma, low-symptomatic adrenocortical cancer).