Electron- and Positron-Emitting Radiolanthanides for Therapy: Aspects of Dosimetry and Production

Journal of Nuclear Medicine

Frank Rösch¹  Helena Uusijärvi¹  Eva Forssell-Aronsson¹  Helmut R. Maecke¹  Peter Bernhardt¹ 

关键词: radiolanthanides;    radionuclide therapy;    dosimetry;    production;   

DOI  :  

学科分类：医学（综合）

来源: Society of Nuclear Medicine

【 摘 要 】

All lanthanides have similar chemical properties regarding labeling. Therefore, radiolanthanides that have been used for therapy, such as 153Sm and 177Lu, might easily be replaced with other radiolanthanides. The aim of this work was to investigate the suitability of electron- and positron-emitting radiolanthanides for radionuclide therapy with reference to dosimetry and production possibilities. Methods: Radiolanthanides with half-lives of 1 h to 15 d, stable or long-lived daughters, and limited photon emission were selected. The ratio of the absorbed dose rate to the tumors and the normal tissue () was calculated for different tumor sizes and compared with thevalues for 90Y and 131I. The normal tissue and tumors were simulated as an ellipsoid and spheres, respectively. Thevalues depend on the physical parameters of the radionuclides, the tumor size, and the ratio between the activity concentrations in the tumor and normal tissue (TNC). Results: 153Sm, 161Tb, 169Er, 175Yb, and 177Lu had the highestvalues for most of the tumor sizes studied. Among these radiolanthanides, 161Tb and 177Lu are the only ones that can be produced no-carrier-added (nca) and with high specific activities. The Auger-electron emitters 161Ho and 167Tm had highvalues for tumors weighing less than 1 mg and can be produced nca and with high specific activities. 142Pr, 145Pr, and 166Ho showedvalues similar to those of 90Y. 166Ho is generator produced and can be obtained nca and at high specific activities. 143Pr, 149Pm, 150Eu, 159Gd, 165Dy, 176mLu, and 179Lu had highervalues than did 90Y for all tumor sizes studied, but only 149Pm can be produced nca and at high specific activities. The other electron-emitting radiolanthanides and the positron-emitting radiolanthanides showed lowvalues for all tumor sizes because of the high photon contribution. Conclusion: The low-energy electron emitters 161Tb, 177Lu, and 167Tm might be suitable for radionuclide therapy. The Auger-electron emitter 161Ho might not be suitable for systemic radionuclide therapy (intravenous injection) because of its short half-life but might be suitable for local therapy (e.g., in body cavities). If higher electron energy is needed, 149Pm or 166Ho might be suitable for radionuclide therapy.

【 授权许可】

Unknown