Endocrine Abstracts

Introduction: Adrenal incidentalomas (AIs) are defined as adrenal masses measuring 10 mm or more in diameter, incidentally discovered on imaging exams performed for a non-adrenal disorder. The aim of this study is to provide a clinical and imagiological characterization of patients diagnosed with AIs followed in our institution.

Methods: We conducted an observational and retrospective study that included patients with AIs evaluated at our institution between 2008 and 2018.

Results: Two hundred and twenty-three patients were included, 63.1% of the female gender (n=147), with a median age at diagnosis of 62.6±11.3 years and a mean follow-up of 43.2±29.6 months. The most prevalent comorbidities were hypertension (76.7%), followed by dyslipidemia (47.6%), obesity (46.6%), osteoporosis (38.2%), glucose intolerance/type 2 diabetes mellitus (32.2%). The imaging technique that first diagnosed the adrenal lesion was abdominal computed tomography (CT) in 78.5%, chest CT in 6.7%, abdominal ultrasound in 6.3%, abdominal magnetic resonance in 4.9%, kidney ultrasound in 2.2% and lumbar spine CT in 1.3% of patients. The majority of AI were unilateral (88.8%, n=198), with a mean maximal diameter at the time of diagnosis of 23.5 mm (10–120 mm) and localized on the left adrenal gland (n=131). Patients with bilateral disease had a maximal diameter at the time of diagnosis of 20.7 mm in the right adrenal gland (10–30 mm) and 16.2 mm (13–21 mm) in the left adrenal gland. At the time of diagnosis, 14 patients presented AI with a maximal diameter above 40 mm. Among the 223 cases, 28 primary adrenal dysfunction was documented (pheochromocytoma 7, primary hyperaldosteronism 9, cushing’s syndrome 5 and autonomous cortisol secretion in 7). Thirty three patients underwent adrenalectomy, 24 for functional autonomy and 9 according to size criteria (>40 mm). The incidence of malignancy was 1.3% (n=3) and in these tumour size exceeded 40mm. Pathology results revealeds 20 cortical adenomas, 7 pheochromocytomas, 2 myelolipomas, 1 pulmonary adenocarcinoma metastasis, 1 benign oncocytoma, 1 adrenocortical carcinoma and 1 retroperitoneal ganglioneuroma.

Conclusions: In our experience the majority of Adrenal incidentalomas (AIs) are benign and non-secretory. Malignancy was exceedingly rare and suggested by adrenal lesion size and radiological phenotype. AI investigation and follow up by endocrinologists is warranted in order to optimize patient care and better understand this prevalent condition.