Endocrine Abstracts

Adrenal masses are common incidental radiological findings. It has been estimated that as many as 10–20% of patients with essential hypertension may suffer from undiagnosed primary aldosteronism (PA). In patients who have both adrenal incidentaloma, which the functioning one must be identified. We report a case where an unilateral PA was detected on ¹⁸F-fluorodexoyglucose (FDG)-positron emission tomography (PET), and comfirmed by adrenal venous sampling.

A 53-year-old man was referred to the clinic due to bilateral adrenal masses (right sized 1 cm, left 2.5 cm) on the abdominal computed tomography. The patient was receiving chemotherapy due to a colon cancer postoperatively. Subsequently, whole body FDG–PET was performed, and showed a focal increase of FDG uptake at the right adrenal adenoma. Serum aldosterone-renin ratio was 104, and not suppressed by captopril. As suspection of PA, adrenal venous sampling was performed. It revealed the aldosterone/cortisol ratio was 33 times higher on right adrenal side than left, which consistent with the result of FDG uptake. He was underwent laparascopic mass excision of right adrenal adenoma.

Therefore, we propose that FDG–PET can be useful diagnostic tool for identifying functional adrenal mass instead of adrenal venous sampling.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.