Endocrine Abstracts

Background and aim: Incidentally discovered adrenal masses (adrenal incidentalomas (AI)), generally 1 cm or more in diameter, are mostly benign and asymptomatic and are often considered as nonfunctional tumors. The aim of this study was to perform the imaging characteristics, endocrinologic screening and histologic diagnoses of adrenal incidentaloma cases encountered in our institute.

Methods: This retrospective evaluation of patients with AI includes 543 cases between 2001 and 2013. Patients were 228 males and 315 females, aged between 18 and 105 years (median, 57 years).

Results: Mass size (computed tomography measurement) ranged from 5 to 150 mm (median, 21 mm). Hormonal work-up demonstrated that 76.2% of the masses were nonsecretory, 11.4% were pheochromocytoma, 9.9% were defined as subclinical Cushing’s syndrome (SCS), 1.6% Cushing’s syndrome, 0.5% were hyperaldosteronism and 0.5% patient concomitant secretion of glucocorticoid, mineralocorticoid, androgen, and catecholamines. Adrenalectomy was performed in 108 patients with removal of 28 adrenocortical adenomas (26%), 15 pheochromocytoma (14%), 14 adrenocortical carcinomas (13%) and other less frequent tumor types. In patients with SCS; the rate of abnormalities was as follows: cortisol nonsuppressibility after 1 mg dexamethasone in 100%, above normal urinary free cortisol in 36.4%, and low ACTH in 28.6%. No significant difference was observed in the ages among patients with adrenocortical carcinoma and adrenocortical adenomas (48.7±10.7; vs 55.6±11.6 years; P=0.066). Patients with adenomas were significantly smaller than carcinomas (32±10 vs 54±35; P=0.037). The survival of patients with AI that were functional evaluated was higher than those that were not (respectively; median 149, 53 months).

Conclusion: Based on these findings, an optimal diagnostic approach to an adrenal incidentaloma would consider the results of the initial biochemical and radiographic evaluations. Endocrine evaluation should be performed in all patients to identify silent states of hormone excess.