摘要
目的:评价3'-脱氧-3'-18F-氟代胸苷(18F-FLT)和18F-氟代脱氧葡萄糖(18F-FDG)PET早期肺腺癌显像在放射治疗疗效中的作用。方法:将18只荷肺腺癌小鼠随机分为18F-FLT组和18F-FDG组,各组又随机配对分为A、B、C3组,每组3只。A组为对照组,未进行任何治疗;B组于实验前1 d采用异氟醚麻醉后,固定于直线加速器下,对小鼠肿瘤部位进行放射治疗,单次剂量2000 c Gy,能量6 MV,射线类型为X射线;C组于实验前2 d同样对小鼠肿瘤部位进行放射治疗,操作方法及放射治疗剂量同B组。经小鼠尾静脉注入18F-FLT和18F-FDG后行Micro PET显像,并处死小鼠取各器官用井形探测仪测定生物分布。结果:荷肺腺癌小鼠的生物分布研究中发现,肿瘤部位18F-FLT及18F-FDG摄取较高,肿瘤对肌肉及肺的T/NT比值均>2,18F-FLT及18F-FDG PET对肿瘤显像清晰。放射治疗后肺腺癌18F-FLT摄取较对照组明显降低,而18F-FDG摄取变化不明显。PET显像18F-FLT组在放射治疗24 h和48 h后T/NT值明显降低且与放射治疗前对比有明显差异(t=2.017,P<0.05)。18F-FDG组则无明显差异。结论:18F-FLT可被肺部恶性肿瘤摄取,其特异度高于18F-FDG。放射治疗引起的18F-FLT摄取变化较18F-FDG灵敏,放射治疗后18F-FLT摄取降低较18F-FDG明显,因而18F-FLT是一种监测恶性肿瘤放射治疗疗效的有效示踪剂。
Objective： To evaluate the early efficacy of 18F-FLT and 18F-FDG PET imaging in assessing the tumor the response of radiotherapy for lung adenocarcinoma. Methods： Eighteen mice bearing lung adenocarcinoma were randonlly divided into two groups according to the different tracers （18F-FLT and 18F-FDG）, every group was divided into three parts, the first and second groups were treated with 6 Mv X-ray irradiation of 2000 cGy one fraction in the first and second day before the experiment , the third was control group. All mice were injected with18F-FLT or 18F-FDG by tail vein. At 30 min after tracers injection, body distribution and PET imaging were performed. Results： The body distribution study in murine model of lung adenocarcinoma shows considerable uptake of 18F-FLT and 18F-FDG in tumor was observed. The ratio of tumor to muscle, tumor to lung were all above 18F-FLT uptake in murine model of lung adenocarcinoma after irradiation was significantly lower than that of control group. PET imaging after radiotherapy shows the T/NT value of FLT group was significantly lower than the control group after 24h, 48h（t=2.017, P〈0.05）. Conclusion： Our experimental studies shows that the uptake of 18F-FLT in pulmonary malignant tissues is higher than that in normal tissues, thus the pulmonary neoplasm can be identified accurately with PET imaging. The decrease in tumor 18F-FLT uptake after radiotherapy was more pronotinced than that of 18F-FDG. Therefore,18F-FLT is a promising PET tracer for monitoring response to radiotherapy in oncology.
出处
《中国医学装备》
2015年第6期70-74,共5页
China Medical Equipment
