Localization procedures in pheochromocytoma and neuroblastoma.

Localization procedures are required in catecholamine-producing tumors after clinical and biochemical confirmation. Computed tomography, ultrasound and/or 131I-metaiodobenzylguanidine (131I-MIBG) scintigraphy was performed in patients with pheochromocytoma, neuroblastoma and metastases of carcinoid tumors. Whereas computed tomography and ultrasound reflect morphological abnormalities, adrenomedullary scintigraphy depends on hormonal activity and other factors. 131I-MIBG scintigraphy has the advantage of detecting extraadrenal, multilocular and malignant pheochromocytomas. Especially small lesions and tumor tissue in bone marrow in children with neuroblastoma can be visualized more easily.