Combination Radionuclide Therapy Using 177Lu- and 90Y-Labeled Somatostatin Analogs

Journal of Nuclear Medicine

Roelf Valkema¹  Bert F. Bernard¹  Eric P. Krenning¹  Wout A.P. Breeman¹  Marion de Jong¹ 

[1] Department of Nuclear Medicine, Erasmus Medical College, Rotterdam, The Netherlands Department of Nuclear Medicine, Erasmus Medical College, Rotterdam, The Netherlands Department of Nuclear Medicine, Erasmus Medical College, Rotterdam, The Netherlands

关键词: ⁹⁰Y;    ¹⁷⁷Lu;    somatostatin analogs;    tumor size;    peptide-receptor radionuclide therapy;   

DOI  :  

学科分类：医学（综合）

来源: Society of Nuclear Medicine

【 摘 要 】

Peptide receptor-targeted radionuclide therapy of somatostatin receptor-expressing tumors is a promising application of radiolabeled somatostatin analogs. Suitable radionuclides are 90Y, a pure, high-energy β-emitter (2.27 MeV), and 177Lu, a medium-energy β-emitter (0.5 MeV) with a low-abundance γ. Methods: Lewis rats, each bearing both a small (approximately 0.5 cm2) and a large (7–9 cm2) somatostatin receptor-positive rat pancreatic CA20948 tumor in their flanks, were used. We investigated the radiotherapeutic effects of [90Y-tetraazacyclododecanetetraacetic acid (DOTA),Tyr3]octreotide, [90Y-DOTA,Tyr3]octreotate, [177Lu-DOTA,Tyr3]octreotate, and the combination of 90Y- and 177Lu-labeled analogs at the same tumor radiation dose (60 Gy). Results: Radiotherapeutic effects of the 90Y- and 177Lu-labeled analogs were found in the rat tumor model. In these animals bearing tumors of different sizes, the antitumor effects of the combination of 50% 177Lu- plus 50% 90Y-analogs were superior to those in animals treated with either 90Y- or 177Lu- analog alone. In smaller tumors, the 90Y radiation energy was not completely absorbed in the tumor, whereas in larger tumors the increased number of clonogenic tumor cells at the fixed level of absorbed dose may account for the failure of 177Lu alone to go completely into remission. Conclusion: This study shows the superior antitumor effects of the combination of 177Lu- and 90Y-somatostatin analogs when compared with either 90Y- or 177Lu-analog alone in animals bearing tumors of various sizes.

【 授权许可】

Unknown