Buus Simon, Grau Cai, Munk Ole Lajord, Rodell Anders, Jensen Kenneth, Mouridsen Kim, Keiding Susanne
PET Centre, Department of Oncology, Aarhus University Hospital, Aarhus, Denmark.
Radiother Oncol. 2006 Mar;78(3):262-9. doi: 10.1016/j.radonc.2006.02.013. Epub 2006 Mar 20.
Previously, we showed that the net metabolic clearance of 11C-methionine of the parotid gland, K, calculated from dynamic 11C-methionine PET, can be used as a measure of parotid gland function. The aim of this study was to investigate by dynamic 11C-methionine PET the individual radiation dose response relationship of parotid glands in head and neck cancer patients.
Twelve head and neck cancer patients were examined by dynamic 11C-methionine PET after radiotherapy. Parametric images of K were generated, co-registered and compared voxel-by-voxel with the 3D radiation dose plan within the parotid gland to assess the individual radiation dose-function relationship.
In each patient, voxel-values of K decreased with increasing radiation dose. Population based analysis showed a sigmoid dose response relationship of parotid gland, from which we estimated a threshold radiation dose of 16 Gy and a mean TD50 of 30 Gy. TD50 ranged from 7 to 50 Gy in the group of patients.
Individual radiation dose response of parotid glands can be measured by dynamic 11C-methionine PET. The dose response analysis revealed a sigmoid relationship, a threshold radiation dose of 16 Gy, and a mean TD50 of 30 Gy.
此前，我们发现，根据动态11C-蛋氨酸PET计算得出的腮腺11C-蛋氨酸净代谢清除率K，可用于衡量腮腺功能。本研究旨在通过动态11C-蛋氨酸PET研究头颈癌患者腮腺的个体辐射剂量反应关系。
12名头颈癌患者在放疗后接受了动态11C-蛋氨酸PET检查。生成K的参数图像，进行配准，并与腮腺内的3D辐射剂量计划逐体素进行比较，以评估个体辐射剂量-功能关系。
在每位患者中，K的体素值随辐射剂量增加而降低。基于人群的分析显示腮腺呈S形剂量反应关系据此我们估计阈辐射剂量为16 Gy，平均TD50为30 Gy。该组患者的TD50范围为7至50 Gy。
可通过动态11C-蛋氨酸PET测量腮腺的个体辐射剂量反应。剂量反应分析显示呈S形关系，阈辐射剂量为16 Gy，平均TD50为30 Gy。
