Comparison of [177Lu-DOTA0,Tyr3]-Octreotate and [177Lu-DOTA0,Tyr3]-Octreotide for Receptor-Mediated Radiation Therapy of the Xenografted Human Midgut Carcinoid Tumor GOT1
2008 (English)In: Cancer Biotherapy and Radiopharmaceuticals, ISSN 1084-9785, E-ISSN 1557-8852, Vol. 23, no 1, 114-120 p.Article in journal (Refereed) Published
The aim of this study was to compare the tumor uptake versus time and the tumor response in nude mice transplanted with a human midgut carcinoid (GOT1), when treated with either [177Lu-DOTA0,Tyr3]-octreotide or [177Lu-DOTA0,Tyr3]-octreotate and to evaluate if plasma chromogranin A (P-CgA) was a reliable marker of tumor response. The tumor uptake and retention of activity of a single intravenous (i.v.) dose (15 MBq) of [177Lu-DOTA0,Tyr3]-octreotate or [177Lu-DOTA0,Tyr3]-octreotide were compared in nude mice xenografted with GOT1. The activity concentration 24 hours after injection was significantly higher in animals given [177Lu-DOTA0,Tyr3]-octreotate versus [177Lu-DOTA0,Tyr3]-octreotide (16% ± 1.4% of injected activity per gram [%IA/g] vs. 8.1% ± 2.1% IA/g, mean ± standard error of the mean) (p = 0.00061). The mean absorbed dose was higher in animals given [177Lu-DOTA0,Tyr3]-octreotate (46 ± 4.3 vs. 17 ± 3.4 Gy). The reduction of tumor volume was accordingly more prominent in animals given [177Lu-DOTA0,Tyr3]-octreotate than in animals given [177Lu-DOTA0,Tyr3]-octreotide (p = 0.003). The mean tumor volume for animals given [177Lu-DOTA0,Tyr3]-octreotate was reduced to 3% of its initial value. P-CgA values were strongly correlated with tumor volume. Octreotate seems to be a more suitable somatostatin analog than octreotide for receptor-mediated radiation therapy. P-CgA is a simple, accurate method for the estimation of tumor response in this animal model.
Place, publisher, year, edition, pages
2008. Vol. 23, no 1, 114-120 p.
octreotate, octreotide, somatostatin receptor, carcinoid, chromogranin A
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-152597DOI: 10.1089/cbr.2007.0421ISI: 000254025100012OAI: oai:DiVA.org:uu-152597DiVA: diva2:413531