Aim: The aim of the study was to evaluate the current role of I-123-MIBG scintigraphy in the detection and follow-up of patients with paragangliomas. Materials and Methods: 117 patients were... Show moreAim: The aim of the study was to evaluate the current role of I-123-MIBG scintigraphy in the detection and follow-up of patients with paragangliomas. Materials and Methods: 117 patients were referred for diagnostic I-123-MIBG scintigraphy based on a strong clinical suspicion, positive familial history and genetic testing, or for follow-up of paragangliomas. I-123-MIBG images were analyzed and correlated with In-111-octreotide scintigraphy, CT or MRI results. Accuracy of the imaging method was calculated per patient and per tumor per site. Results: A total of 117 patients were referred for I-123-MIBG diagnostic imaging; 80 patients were diagnosed with paraganglioma; 66 patients had a single neuroendocrine tumor and 14 patients multiple tumors. The total number of all lesions in these patients was 172. I-123-MIBG scintigraphy demonstrated 65 lesions in 56 patients (overall sensitivity: 56.3%, specificity: 84%). Lesion-per-site analysis revealed that sensitivity and specificity significantly varied per tumor site (lowest sensitivity for the head and neck: 17.5% and lowest specificity for the abdomen: 87.5%). Hormones were elevated in 85 patients: 55 I-123-MIBG tumors were positive and 35 tumors were negative. In 16 patients (13.7%) with a genetic burden and a single neuroendocrine tumor, I-123-MIBG whole-body imaging was successful at detecting a second tumor. In 2 patients (1.7%) with paragangliomas, I-123-MIBG unexpectedly detected metastases, so the restaging was properly done. Conclusion: I-123-MIBG scintigraphy remains important in pheochromocytoma and functioning neuroendocrine tumors. The value of I-123-MIBG scintigraphy is high in familial syndromes with multiple neuroendocrine tumors at different sites, multifocal tumors, and relapsing and metastatic disease. Copyright (C) 2009 S. Karger AG, Basel Show less
I-123-meta-iodobenzyl-guanidine (I-123-MIBG) scintigraphy is used to visualize and quantify the sympathetic nerve activity. Although it has been used since 1980 to identify myocardial innervation,... Show moreI-123-meta-iodobenzyl-guanidine (I-123-MIBG) scintigraphy is used to visualize and quantify the sympathetic nerve activity. Although it has been used since 1980 to identify myocardial innervation, it is not yet regarded a routine sympathetic imaging agent in this respect. The lack of large multicentre studies and the presence of variations in the protocols that are used for planar MIBG acquisition confines the comparability of study results and application of normal values. Therefore, the aim of this study was to assess the variations in mathematical methods that are currently used to quantify the heart-to-mediastinum ratio and washout rate (WOR). In addition, normal values were evaluated in concordance with these methods. A systematic literature search yielded 169 unique manuscripts, of which 30 contained a complete description of the acquisition protocol for planar MIBG acquisition, image analysis and quantification of the parameters. The results indicate not only large variations in mathematical methods, but also in various aspects of the protocols that are used during acquisition. In many manuscripts method-specific normal values were used; however, these values were generally generated from small, single-centre studies. This study stresses the need to produce guidelines to achieve a standardized method for MIBG acquisition, image analysis and methods to quantify parameters. Nucl Med Commun 31:617-628 (C) 2010 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins. Show less
