Wang Zheng, Wang Juan, Yao Yongyi, Wang Feng, Fan Qiang, Zhao Ruifeng
Department of Nuclear Medicine, Jincheng Anthracitic Coal Mining Group General Hospital, Jincheng, Shanxi 048006, P.R. China.
Exp Ther Med. 2021 Dec;22(6):1438. doi: 10.3892/etm.2021.10873. Epub 2021 Oct 12.
There is still controversy about quantitatively evaluating the therapeutic effect of radioactive low-activity iodine125 seeds (I seeds). In the present study, a paired VX tumor model in a rabbit hind leg muscle was established, which is virus-induced anaplastic squamous cell carcinoma characterized by hypervascularity, rapid growth and easy propagation in the skeletal muscle. I seeds with 0.4 and 0.7 mCi activity were implanted into the left and right legs, respectively, using a radiation treatment planning system under positron emission tomography (PET)/computed tomography (CT) guidance. PET/CT scans and hematoxylin and eosin staining were observed at 72 h and 2 and 4 weeks after implantation to assess the therapeutic effect. The results showed that the average tumor length and standard uptake value (SUV) decreased over time, and both I seed groups achieved therapeutic effects at 4 weeks post-implantation. Quantitative evaluation of tumor inhibition rate, SUV variation and tumor marker ratio (Bcl-2/Bax) suggested that 0.7 mCi I seeds were more suitable than 0.4 mCi seeds in a clinical setting.
关于定量评估放射性低活度碘125种子（I种子）的治疗效果仍存在争议。在本研究中，建立了兔后腿肌肉中的配对VX肿瘤模型，该模型为病毒诱导的间变性鳞状细胞癌，其特征为血管丰富、生长迅速且易于在骨骼肌中扩散。在正电子发射断层扫描（PET）/计算机断层扫描（CT）引导下，使用放射治疗计划系统将活度为0.4和0.7毫居里的I种子分别植入左右腿。在植入后72小时以及2周和4周时进行PET/CT扫描和苏木精-伊红染色，以评估治疗效果。结果显示，平均肿瘤长度和标准摄取值（SUV）随时间下降，且两个I种子组在植入后4周均达到治疗效果。对肿瘤抑制率、SUV变化和肿瘤标志物比率（Bcl-2/Bax）的定量评估表明，在临床环境中，0.7毫居里的I种子比0.4毫居里的种子更合适。
