Statistics from Altmetric.com
A 70-year-old woman with controlled type 2 diabetes mellitus and hypertension presented for evaluation of chronic abdominal discomfort. An incidental 3.2×3.5×3 cm left adrenal mass was identified on CT. Physical examination revealed obesity stage 2 without a Cushingoid appearance and controlled hypertension with a regular heart rate. Biochemical evaluations for Cushing syndrome, primary aldosteronism and pheochromocytoma were negative. A 1-year follow-up CT of the adrenal glands with washout showed a larger left-sided adrenal mass, measuring 4.3x3.4x3 cm (figure 1A). The attenuation values of the mass were indeterminate: non-contrast, 15 Hounsfield unit (HU); portal venous, 70 HU; delayed, 42 HU; absolute washout, 51%. MRI of the abdomen confirmed the left adrenal mass (figure 1B,C). Given the rapidly increasing size, malignancy was suspected and a whole-body positron emission tomography/CT scan using 18F-fluorodeoxyglucose (18F-FDG) was performed, which demonstrated (figure 1D,E) an 18F-FDG avid adrenal mass (standardized uptake values (SUV)max: 6.16) with increased activity compared with the liver background (SUVmax: 2.4). Adrenal incidentalomas are lesions that are detected on imaging performed during the evaluation of non-adrenal disease, with a prevalence of ~4%–10% of all scans.1 2 Patients with an incidentaloma should undergo evaluation for Cushing syndrome or autonomous cortisol secretion, pheochromocytoma, primary aldosteronism if hypertensive or a malignant tumour (particularly if size >4 cm).3 Non-functional adrenal adenomas rarely show increased 18F-FDG activity; their SUV should be compared with the average 18F-FDG uptake by the liver. Given the size of the adrenal mass and the increased 18F-FDG uptake, a left laparoscopic adrenalectomy was performed to rule out adrenocortical carcinoma. Microscopic examination showed mainly clear cell pattern with a focal eosinophilic component, and a Weiss score of zero, consistent with a benign adrenocortical adenoma (figure 2). The patient did well after surgery.
Adrenal incidentalomas are lesions that are detected on imaging performed during the evaluation of non-adrenal disease, with a prevalence of ~4%–10%.
Non-functional adrenal adenomas rarely show increased 18F-FDG activity; their SUV should be compared with the average 18F-FDG uptake by the liver.
Contributors FH-S, GZP, CAS and JB were involved in the planning, conduct, reporting, conception and design, acquisition of data or analysis and interpretation of data.
Competing interests None declared.
Patient consent Obtained.
Provenance and peer review Not commissioned; externally peer reviewed.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.