[Intraoperative measurement of radiation dosage following 123-iodine meta-iodobenzylguanidine scintigraphy in surgical therapy of metastatic pheochromocytoma].

We investigated whether preoperative injection of 123-Jod-MIBG might be useful for intraoperative staging of chromaffine tumor cells. This was performed in a 46 year old patient in whome the diagnosis of a malignant pheochromocytoma had been established by 123-Jod-MIBG image and in catacholamine secretion. The rational for intraoperative staging of this patient was a discrepancy between computer tomography (CT) and the radio nuclide imagine. Intraoperative the tumor mass was identified with an activity of 10 x 10(4) Imp/sec as compared to normal tissue (15 x 10(2). A lymph node metastasis was found to be identified only by prior MIBG imagine and not by CT scanning. We thus conclude that intraoperative employment of this single probe measurement method might help to identify chromaffine tumor cells that have not been located fully by CT.