A Large Adrenal Tumor With Marked ¹⁸F-Fluorodeoxyglucose Uptake

Abstract

A 56-year-old woman was referred for evaluation of an incidentally discovered adrenal mass. She experienced no symptoms of weight loss, headache, sweating, palpitations, pallor, anxiety, menstrual abnormalities, or mood changes; had no known history of cancer or hypertension; and was not taking any medications. On physical examination, her blood pressure was 135/73 mm Hg, and her heart rate was 82/min. There was no truncal or facial obesity, acne, striae, hirsutism, or proximal muscle weakness. Laboratory analysis showed normal blood cell counts and levels of electrolytes, liver enzymes, and lactate dehydrogenase. Further biochemical evaluation revealed normal levels of plasma and urinary cortisol, serum aldosterone and 17-hydroxyprogesterone, and urinary metanephrines. A computed tomography (CT) scan revealed a 5.5 × 4.3-cm left adrenal tumor with heterogeneous appearance, a hypodense central area, and irregular margins, with a density of 36 Hounsfield units (HU). Relative and absolute adrenal washout values (a measure of the disappearance of contrast media from a mass after 10 minutes) were 23% and 47%, respectively. A positron emission tomography (PET)/CT scan using 18 F-fluorodeoxyglucose ( 18 F-FDG) was performed for further tumor characterization (Figure). Figure. Computed tomography (left) and positron emission tomography/computed tomography (right) imaging of the patient. WHAT WOULD YOU DO NEXT? A. Perform a biopsy of the mass B. Order a repeat CT scan in 3-6 months C. Request a surgical consult for adrenalectomy D. Perform adrenal magnetic resonance imaging Clinical Review & Education

PET Scans With 18F-Fluorodeoxyglucose to Diagnose Adrenal Tumors

“…To the Editor In the JAMA Clinical Challenge of a patient with a large adrenal tumor, we question the need for a positron emission tomography (PET)/computed tomography (CT) scan using 18 F-fluorodeoxyglucose ( 18 F-FDG) in establishing the need to proceed with surgery. Based on size (5.5 cm), presence of irregular margins, and a central hypodense area, the suspicion for malignancy was already high.…”