Endocrine Abstracts

Introduction: Computed tomography (CT) scan is the first imaging method used to characterize adrenal lesions in order to select patients for surgical treatment. Our aim was to specify the performance of this tool in the work up of adrenal masses (AM) recruited in a department of Endocrinology.

Material and methods: This retrospective study included 100 patients hospitalized in our department between 2008 and 2014 for adrenal tumors. After a systematic exclusion of pheochromocytomas, the criteria used to define adrenal benign lesions were either histology (n=24/52) or lack of volume increase after two years follow-up (n=30). CT scan features were evaluated for tumor size, spontaneous density (SD), and absolute wash out (AWO). When there is a discrepancy, a blind proofreading was done by an independent radiologist.

Results: Among 100 cases: 54 were considered as adenomas, 22 as carcinomas, 4 as adrenal metastases and 20 as benign tumors. Positive predictive value (PPV) and negative predictive value (PNV) were respectively 96 and 75% for a tumor size ≤40 mm, 100 and 75% for a SD≤10 UH, and 100% and 88.8% for an AWA > 60%.

Discussion and conclusion: The abdominal CT scan is a fundamental tool which can differentiate benign from malignant adrenal tumors as it offers specific features characterizing adenomas. Actually, a tumor size less than 40 mm with a SD less than 10HU and an AWO>60% plead for the diagnosis of a benign process with a PPV of 100%.