How will you localize pheochromocytoma :: (A) Clinical examination, (B) VMA excretion, (C) CT scan, (D) X-ray
Answer is C. Radiologic studies are useful to localize Pheochromocytoma and to assess the extent of spread once the diagnosis has been made with biochemical tests. CT scans are 85 to 95% sensitive and 70 to 100% specific for pheochromocytomas. CT scans do not provide functional information and cannot definitively diagnose pheochromocytomas. MRI scans are 95% sensitive and almost 100% specific for pheochromocytomas because these tumors have a characteristic appearance on T2-weighted images or after gadolinium. MRI is also the study of choice in pregnant women as there is no risk of radiation exposure. Ref : Lal G. (2010). Chapter 38. Thyroid, Parathyroid, and Adrenal. In T.R. Billiar, D.L. Dunn (Eds), Schwaz's Principles of Surgery, 9e.