Intraoperative localization of malignant pheochromocytoma by 123-i-metaiodobenzylguanidine single probe measurement

Metaiodobenzylguanidine (MIBG) imaging is a well-established method for locating intra- and extraadrenal pheochromocytomas. We investigated whether preoperative injection of 123-I-MIBG might be useful for intraoperative staging of chromaffine tumor cells. This was performed in a 46-year-old patient in whom the diagnosis of a malignant pheochromocytoma had been established by 123-I-MIBG imaging and enhanced catecholamine secretion. The rationale for intraoperative staging in this patient was a discrepancy between computed tomography (CI) of the abdomen and the radionuclide imaging, because scintigraphy revealed a mass with MIBG uptake in the right lower abdomen that could not be visualized b…