Long term follow-up of patients with adrenal incidentalomas--a single center experience and review of the literature.

BACKGROUND

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.

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.