Daemen B J, Elsinga P H, Paans A M, Wieringa A R, Konings A W, Vaalburg W
PET Center, University Hospital, State University, Groningen, The Netherlands.
J Nucl Med. 1992 Mar;33(3):373-9.
The potential use of PET to monitor radiotherapeutic effects on tumors has been evaluated with L-[1-11C]tyrosine and 18FDG. Single x-ray doses of 10, 30, or 50 Gy have been applied to rhabdomyosarcoma tumors growing in the flank of rats. Dose-dependent reductions of tracer uptake were registered by PET 4 and 12 days after treatment. These later effects on tracer uptake appeared to correlate with changes in tumor volume. Therefore, PET using L-[1-11C]tyrosine and 18FDG is suitable to monitor kinetics of tumor growth and tumor regression after radiotherapy. Direct effect on tracer uptake was not observed within 8 hr after irradiation. This indicates that, using PET, early predictions on the outcome of radiotherapy are not possible. When combining a radiation treatment with hyperthermia, radiation-induced inhibition of tumor growth was clearly enhanced. Tracer uptake remained at the pretreatment value, possibly due to invasion of host cells. From these experiments, it can be concluded that it is difficult to monitor a combined treatment of radiation and hyperthermia by PET.
已使用L-[1-¹¹C]酪氨酸和¹⁸F-FDG评估了正电子发射断层扫描（PET）监测放疗对肿瘤疗效的潜在用途。已对生长在大鼠侧腹的横纹肌肉瘤肿瘤施加了10、30或50 Gy的单次X射线剂量。治疗后4天和12天，PET记录到示踪剂摄取呈剂量依赖性降低。这些对示踪剂摄取的后期影响似乎与肿瘤体积的变化相关。因此，使用L-[1-¹¹C]酪氨酸和¹⁸F-FDG的PET适用于监测放疗后肿瘤生长和肿瘤消退的动力学。照射后8小时内未观察到对示踪剂摄取的直接影响。这表明，使用PET无法对放疗结果进行早期预测。当将放射治疗与热疗相结合时，辐射诱导的肿瘤生长抑制明显增强。示踪剂摄取保持在预处理值，这可能是由于宿主细胞的侵入。从这些实验可以得出结论，通过PET监测放疗和热疗的联合治疗很困难。
