INTRODUCTION: Adrenal incidentalomas (AIs) constitute an emerging clinical entity due to the increased use of abdominal imaging for diagnostic purposes. Most often it consists of benign-nonfunctioning lesions and an increase in size during follow-up is reported in about 9% (0-26%), whereas their functional evolution is rare.
MATERIALS AND METHODS: Sixty-four patients (22 males and 42 females; mean age 61.6 ± 1.2 years), with AIs and follow-up of 3.1 ± 0.4 years (range 0-19) were retrospectively evaluated. The patients underwent basal and dynamic evaluation of the hypothalamic-pituitary-adrenal axis, renin-angiotensin-aldosterone system and adrenomedullary function. Mass enlargement and adrenal hyperfunction were estimated at yearly intervals.
RESULTS: Adrenalectomy was performed in 5 patients (4 benign cortical adenomas and 1 pheochromocytoma). Abnormal manifestation, based on clinical, laboratory and histological evaluation, was observed in 4 patients [1 (1.56%) with SCS, 2 (3.12%) with pheochromocytoma and 1 (1.56%) with aldosteronoma], 3 of which were diagnosed at their initial evaluation and 1 at the 3 (rd) year of follow-up. The remainders [60 patients (93.75%)] were harbouring a non-secretory mass (8 potential myelolipomas, 8 nodular hyperplasias, 3 cystic lesions). Eleven patients (17.2%) had bilateral AIs. Mass enlargement (5-13 mm) was observed in 9 patients (14%), ≥10 mm 4 (6.25%), while mass shrinkage (5-19 mm) in 3 (4.7%) during follow-up. No hormonal evolution was noticed.
CONCLUSIONS: AIs present usually as benign, non-secretory lesions. Criteria for surgical intervention were met at initial assessment for the majority of AIs. Size alterations during follow-up are uncommon and functional evolution is rare.