A Pheo lurks : Novel approaches for locating occult pheochromocytoma

• Published in: The journal of clinical endocrinology and metabolism 2001-08, Vol.86 (8), p.3641-3646
• Main Authors: PACAK, Karel, GOLDSTEIN, David S, DOPPMAN, John L, SHULKIN, Barry L, UDELSMAN, Robert, EISENHOFER, Graeme
• Format: Article
• Language: English
• Subjects: 3-Iodobenzylguanidine; Adrenal Gland Neoplasms - blood; Adrenal Gland Neoplasms - diagnosis; Adrenal Gland Neoplasms - diagnostic imaging; Adrenal Gland Neoplasms - surgery; Adrenalectomy; Biological and medical sciences; Carrier Proteins - analysis; Dopamine - analogs & derivatives; Dopamine - pharmacokinetics; Endocrine glands. Genital system. Mammary gland; Endocrinology; Epinephrine - blood; Epinephrine - urine; Fluorine Radioisotopes - pharmacokinetics; Humans; Investigative techniques, diagnostic techniques (general aspects); Magnetic Resonance Imaging; Male; Medical sciences; Middle Aged; Neoplasm Recurrence, Local - blood; Neoplasm Recurrence, Local - diagnosis; Neoplasm Recurrence, Local - diagnostic imaging; Norepinephrine - blood; Norepinephrine - urine; Norepinephrine Plasma Membrane Transport Proteins; Normetanephrine - blood; Normetanephrine - urine; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Pheochromocytoma - blood; Pheochromocytoma - diagnosis; Pheochromocytoma - diagnostic imaging; Pheochromocytoma - surgery; Radionuclide investigations; Radiopharmaceuticals; Sensitivity and Specificity; Symporters; Tomography, Emission-Computed; Tomography, X-Ray Computed; Vena Cava, Inferior
• ISSN: 0021-972X; 1945-7197
• DOI: 10.1210/jc.86.8.3641

Most, but not all, pheochromocytomas can be localized by computed tomography or magnetic resonance imaging. Here we introduce two novel approaches for localization of pheochromocytoma in a patient in whom conventional imaging modalities failed to show the tumor. First, we establish that measurements of plasma free metanephrines coupled with vena caval sampling are useful for localizing occult pheochromocytoma, particularly when elevations in plasma catecholamines are slight or intermittent. Second, we show that positron emission tomographic scanning using the imaging agent 6-[18F]fluorodopamine as a substrate for the norepinephrine transporter offers a highly effective method for tumor localization. These novel approaches may be of value in difficult cases, where biochemical and clinical evidence of pheochromocytoma is compelling, yet conventional imaging modalities fail to locate the tumor.