The data on long term natural history of benign nonfunctioning adrenal tumors (NFATs) are lacking. The aim is to identify clinical characteristics associated with tumor growth and progression to mild autonomous cortisol excess over time.

After being informed about the study, all patients with NFAT given written informed consent will underwent a control visit approximatly 10 years after initial visit at the outpateint clinic at the Department of Endocrinology, Diabetes and Metabolic Disease, University Medical Center Ljubljana, Ljubljana, Slovenia. The included patients will be divided in three groups regarding the BMI as follows: BMI < 25 kg/m2, 25-30 kg/m2 and > 30 kg/m2. The investigators will assess clinical, and laboratory parameters and CT findings at the follow up visit and compere them to baseline characteristics.

Inclusion Criteria:

- Patients hospitalized because of NFAI between 2005-2012 at the Department of Endocrinology, Diabetes and Metabolic Disease, University Medical Center Ljubljana, Ljubljana, Slovenia.

Exclusion Criteria:

• age below 18 years
• relatives reported that patient died in the time since hospitalization
• patient did not want a follow up
• patient did not attend follow up appointment
• patient underwent adrenalectomy
• misdiagnosis / missing main information in hospitalization record

Adult patients with diagnosisi of NFAI, hospitalized between 2005-2012 at the Department of Endocrinology, Diabetes and Metabolic Disease, University Medical Center Ljubljana, Ljubljana, Slovenia.