Dalvand Saman, Sadeghi Mahdi
Department of Medical Physics, School of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
Medical Physics Department, School of Medicine, Iran University of Medical Sciences, P.O. Box: 14155-6183, Tehran, Iran.
Appl Radiat Isot. 2022 Apr;182:110113. doi: 10.1016/j.apradiso.2022.110113. Epub 2022 Jan 15.
Due to favorable physical properties of Ce radionuclide [E = 434.6 keV (70.5%) and 580.0 keV (29.5%), E = 145.4 keV, and physical half-life = 32.5 day], a complex including this radionuclide could be a good candidate for palliative therapy of metastatic bone patients and an alternative to 89SrCl2 as a FDA-approved radiopharmaceutical. Because the bone marrow absorbed dose is a limiting factor in the palliative therapy of bone metastases, this study conducted to calculate the bone marrow absorbed dose of Ce-EDTMP complex and compare it with the 89SrCl2 using Monte Carlo simulation. In this study, the GATE Monte Carlo toolkit and two human bone models including vertebra and femur bones were used for simulations. The vertebra and femur bone marrow absorbed dose from Ce-EDTMP were 29.1 and 4.3 mGy/MBq, respectively. Moreover, the vertebra and femur bone marrow absorbed dose from SrCl were 109.2 and 16.3 mGy/MBq, respectively. Bone-to-bone marrow absorbed dose ratio in the vertebra for Ce-EDTMP and SrCl was 34.2 and 11.6, respectively, whereas, this ratio in the femur was 23.8 and 7.5, respectively. Owing to the high bone-to-bone marrow absorbed dose ratio and lower bone marrow absorbed dose than SrCl, Ce-EDTMP could be a promising new complex for palliative therapy of patients with bone metastasis.
由于铈放射性核素具有良好的物理特性[能量E = 434.6 keV（70.5%）和580.0 keV（29.5%），E = 145.4 keV，物理半衰期 = 32.5天]，包含该放射性核素的复合物可能是转移性骨病患者姑息治疗的良好候选药物，并且可作为美国食品药品监督管理局（FDA）批准的放射性药物替代89SrCl2。由于骨髓吸收剂量是骨转移姑息治疗中的一个限制因素，本研究通过蒙特卡罗模拟计算Ce-EDTMP复合物的骨髓吸收剂量，并将其与89SrCl2进行比较。在本研究中，使用GATE蒙特卡罗工具包和包括椎骨和股骨的两个人体骨骼模型进行模拟。Ce-EDTMP对椎骨和股骨骨髓的吸收剂量分别为29.1和4.3 mGy/MBq。此外，SrCl对椎骨和股骨骨髓的吸收剂量分别为109.2和16.3 mGy/MBq。Ce-EDTMP和SrCl在椎骨中的骨与骨髓吸收剂量比分别为34.2和11.6，而在股骨中该比例分别为23.8和7.5。由于骨与骨髓吸收剂量比高且骨髓吸收剂量低于SrCl，Ce-EDTMP可能是骨转移患者姑息治疗中有前景的新复合物。
