RT Journal Article SR Electronic T1 Enhanced Tumor Uptake in Neuroendocrine Tumors After Intraarterial Application of 131I-MIBG JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 2112 OP 2116 VO 46 IS 12 A1 Brogsitter, Claudia A1 Pinkert, Jörg A1 Bredow, Jan A1 Kittner, Thomas A1 Kotzerke, Jörg YR 2005 UL http://jnm.snmjournals.org/content/46/12/2112.abstract AB 131I-labeled metaiodobenzylguanidine (MIBG) is an established treatment modality for neuroendocrine tumors. Because of low tumor doses, it has a predominantly palliative character. Our approach was to investigate whether intraarterial application of 131I-MIBG has the potential to enhance tumor uptake. Methods: Seventeen patients with primary or metastasized neuroendocrine tumors received intraarterial treatment with 131I-MIBG, and 12 of these patients also had intravenous treatment. Every patient underwent intravenous 131I-MIBG whole-body scanning before therapy. For quantification, a tumor–to–whole-body ratio was calculated from the diagnostic and 24-h posttreatment scans. Results: Compared with the intravenous application, intraarterial 131I-MIBG treatment provided an up to 4-fold higher tumor uptake. Mean uptake was enhanced by 69%, but this varied widely between patients. We did not observe any immediate complications from catheterization. Carcinoid-related side effects were noted in 7 of 17 patients and were not different from those seen with intravenous application. Conclusion: Intraarterial treatment with 131I-MIBG is a safe alternative to intravenous application and provides a 69% higher mean tumor uptake. We propose to attempt intraarterial MIBG treatment in every patient to assess its potential benefit.