Radionuclide detection of a pheochromocytoma.

An area of increased radioactivity was visualized superior to the right kidney during the flow phase of a routine radionuclide renal angiography using 99mTc-Sn-DTPA. This same area failed to concentrate the radiopharmaceutical during delayed static images. This sequence suggested a highly vascular mass above the right kidney. The mass proved to be an adrenal pheochromocytoma as was suggested by the radionuclide study.