Clinical, biochemical and hormonal characteristics of 84 patients with incidentally found adrenal tumor (incidentaloma)

In this study we have analyzed 84 patients (58 women, 26 men, mean age 57 +/- 1.1 year) hospitalized in the Department of Nephrology, Endocrinology and Metabolic Diseases of the Medical University of Silesia in Katowice from 01.01.1999 to 30.04.2003 because of incidentally discovered adrenal tumors (incidentaloma). The diameter of the tumors ranged from 8 to 86 mm (mean size 35.4 +/- 1.8 mm). Unilateral tumors were found in 74 patients and bilateral ones in 10 patients. In all patients circadian rhythm of plasma cortisol concentration and urinary cortisol excretion were measured. In 73 patients with a history of hypertension plasma renin activity was estimated in basal conditions and after stimulation by sodium restriction and upright position. Aldosteronemia and urinary metoxycatecholamines excretion were also determined. 45 patients with tumors >4 cm and/or with suspicion of malignancy or hormonal hypersecretion were qualified for surgical treatment. Thirty two patients out of the selected 45 have been operated so far. In two patients histopathological examination confirmed malignancy (adrenocortical carcinoma in one patient and metastatic cancer in the other one). The remaining 30 patients were operated because of size of the adrenal mass (16 patients) or biochemical suspicion of pheochromocytoma (12 patients, 5 of them with the mass size >4 cm) or primary aldosteronism (2 patients). The histological examination confirmed Conn syndrome in two patients and pheochromocytoma in one patient.