Long-term Morphological, Hormonal, and Clinical Follow-up in a Single Unit on 118 Patients with Adrenal Incidentalomas

Objective: To evaluate long-term morphological, functional, and clinical outcome in adrenal incidentalomas.

Design And Methods: A total of 118 patients (77 F and 47 M; age 62.3+/-1.0 years) with adrenal incidentalomas were evaluated at baseline and followed-up for median 3 years (range 1-10 years) by clinical, biochemical, hormonal, and morphological evaluation. Among them, six patients with diagnosis of subclinical Cushing's syndrome (SCS) underwent surgery.

Results: At entry, 86% (n=102) of tumors were nonfunctioning (NF) and 14% (n=16) showed SCS. Comparing NF with SCS patients, a significantly higher percentage of dyslipidemia was found in the group of SCS patients (50 vs 23%, P=0.033). During follow-up, adrenal function remained normal in all NF patients, none of them developed subclinical or overt endocrine disease. The cumulative risk of mass enlargement was globally low (25%), but progressive up to 8 years. SCS was confirmed in all patients, and none of them shifted to overt Cushing's syndrome. The cumulative risk of developing metabolic-cardiovascular abnormalities was globally low (22%), but progressive up to 8 years and new diseases were recorded in the group of NF patients only (three patients with dyslipidemia, four with impaired fasting glucose/impaired glucose tolerance, and three with diabetes mellitus). SCS patients who underwent surgery did not show any significant clinical improvement.

Conclusions: The risk of mass enlargement, hormonal, and metabolic impairment over time is globally low. Conservative management seems to be appropriate, but further prospective studies are needed to establish the long-term outcome of such patients, especially for metabolic status, cardiovascular risk profile and their relationship with endocrine function.