Endocrine Abstracts

Introduction: About 5% of the adult population has adrenal incidentaloma(AI) and its incidence increases with age. AACE guidelines recommend image and hormonal evaluation during 5 years in non functioning AI. The european’s guidelines advise against repeat evaluation in non-secretory AI that present with <4 cm and had benign features. According to recent studies, the risk of developing clinically relevant hormone secretion is <0.3%, in patients with previous non-functioning lesions. The risk of progression to Cushing Syndrome in patients with autonomous cortisol secretion (ACS) is also low (<1%). This study evaluated the risk of developing hypercortisolism or tumor growth in AI of patients followed in an endocrinology department.

Methods: retrospective study of patients with no functioning AI evaluated between 2014-2021 with a minimum follow-up of 3 years. ACS was defined based on post- dexamethasone cortisol value between 1,8-5 μg/d. Significant tumor growth was defined as ≥10mm. Dimensional stability was considered if <5mm variation between successive imaging exams.

Results: Included 84 patients, 42.8% (n=36) female with a median of age of 76(48-93) years-old. At first evaluation the mean AI dimension was 20,9±7,5mm and 20 patients (23.8%) had bilateral tumors. After a mean follow-up of 5,6±1,5 years, each patient was submitted to a mean of 3±1,1 image exams. During follow-up, 2 patients (2.4%) developed ACS and none had been diagnosed with clinical Cushing syndrome. In 68 (81%) patients there was dimension stability, 7 had dimension reduction and 9 had increased size (>5mm). In only 2 patients there was a significant growth: 1 cyst and 1 tumor that has been transformed to an hemorrhagic lesion (pseudocyst) and submitted to surgery.

Conclusion: In this study 2,4% of patients developed ACS. A ≥10 mm growth was only verified in 2 cysts. Adrenal Cysts are rare and usually asymptomatic. AI could suffer hemorrhagic or cystic degeneration and become pseudocyst. Our data are similar to a recent meta-analysis that report no relevant changes in dimension or hormonal function during follow-up of AI.