A pediatric malignant paraganglioma and brief review of the literature.

A 10 years old boy presented to our hospital complaining of belly pain. He had a retroperitoneal mass diagnosed by ultrasound 3 days before. During that time he was found to have slight hypertension. Computed tomography (CT) showed a left retroperitoneal mass with edge enhancement and central necrosis indicating pheochromocytoma (PCC). Vanillymandelic acid (VMA) in the 24 hours urine sample was not elevated. Pheochromocytoma was suspected given his hypertension and the ultrasound and CT findings. Fluorine-18- fluorodeoxy glucose positron emission tomography (18F-FDG PET) showed intense uptake in the left adrenal area (SUVmax 32.9) with a central 18F-FDG uptake defect. Subsequently, left adrenalectomy was successfully performed. Histological examination showed that the tumor was a paraganglioma (PGL) with low-grade malignancy. CONCLUSION Fluorine-18-FDG PET is a highly sensitive method to detect PGL, but could not make a differential diagnosis between PGL and PCC although high uptake of 18F-FDG may indicate malignancy. As our case clearly demonstrates, rare cases of PCC or PGL should be considered in the setting of secondary hypertension.