No abstract

In 1979/80 meta-iodobenzylguanidine (MIBG) was introduced as a radiopharmaceutical agent with high affinity to the adrenal medulla. It could be shown, that scintigraphic imaging with 131J labeled MIBG is a sensitive and highly specific method for localization of pheochromocytoma. In this connection we could demonstrate in 1983 that neuroblastoma can be visualized scintigraphically with MIBG as well. Until now 13 patients were examined with 131J-MIBG by our group: In 10 children with histologically proven neuroblastoma we found a specific enrichment in the tumor area. Besides the primary tumor local recurrence and metastases to bones, bone marrow and brain were detected. There was no neuroblastoma manifestation without MIBG uptake. In 3 patients with tumors other than neuroblastoma no uptake of MIBG was noticed. The results agree with those of other studies: If the physiological pattern of distribution is taken into consideration and if the proper imaging technique is adapted, 131J-MIBG scintigraphy is a highly sensitive and specific method for staging, monitoring of disease and follow-up of neuroblastoma.

No abstract

The sensitivity and specificity of bone marrow scintigraphy in demonstrating skeletal metastases was examined in 40 patients with focal metastases. Radiology and MDP scintigraphy were used as reference methods. Sensitivity depends on the region of the skeleton. False negatives are the rule in parts of the skeleton containing little bone marrow. In relation to the entire bone marrow content, sensitivity is 0.64. The high proportion of false negatives (36%) in the presence of confirmed metastases and the incomplete demonstration of the bone marrow makes marrow scintigraphy unsuitable as a screening method. Occasionally lesions confined to the marrow can be demonstrated when radiographs and bone scintigrams are still negative. In advanced cases, marrow scintigraphy can demonstrate the extent of destruction of the bone marrow. Demonstration of displacement or of an 'empty bone' is evidence of invasion of the bone marrow in patients with tumours. In patients with reduced haematopoiesis of unknown origin or unidentified diffuse skeletal uptake, bone marrow scintigraphy may provide valuable information.

No abstract

The diagnostic value of computed tomography (CT) and iodine-131 meta-iodo-benzylguanidine (MIBG) scintiscanning was studied in nine patients with histologically proved carcinoid tumors of intestinal (n = 4), bronchial (n = 3), or thymic (n = 2) origin. CT scans clearly depicted the tumors and metastases in relation to surrounding vital structures but did not provide findings specific for carcinoids. The appearance on CT of an abdominal soft-tissue mass with a radiating pattern of linear densities was found to be highly suggestive of intestinal carcinoid tumors. I-131 MIBG scintiscans disclosed intense tracer uptake in the tumors and metastases in five patients. MIBG studies correctly depicted nine of nine tumor manifestations in intestinal carcinoids and four of six tumor manifestations in bronchus carcinoids. No MIBG concentration was found in thymus carcinoids. Because of its selective uptake mechanism, I-131 MIBG scintigraphy can allow specific detection and localization of neuroendocrine tumor tissue in patients with suspected carcinoid tumors. MIBG scintigraphy has diagnostic potential as a screening procedure in carcinoid tumors, especially those of intestinal origin.

No abstract

In 1003 patients with a total of 2467 clinically or scintigraphically suspect skeletal parts, conventional x-ray examination at the time of first study resulted in 95% of cases (2331 skeletal parts) in a correct diagnosis. Computed tomography permitted an exact diagnosis in 52% of roentgenologically equivocal findings (136 skeletal parts). In 40% of these patients even by computed tomography metastasis was only suspected, in 8% there were unspecific findings, while by follow-up bone metastasis was proven. In 64.8% of the whole patient collective there were metastatic destructions and in 32.6% of patients benign lesions were found. Superiority of CT compared to conventional x-ray diagnosis resulted from exact demonstration of the intra- and extraosseous extent of lesions and the possibility of density measurements. It depended mainly upon the localisation of the pathologic process.