【摘要】 目的研究18F-FDG对放射性125I粒子治疗恶性肿瘤疗效评价,探索125I粒子对肿瘤细胞杀伤的机理。方法建立A549肿瘤的动物模型(n= 20),分成2组,治疗组(n= 10)肿瘤内植入放射性125I粒子,对照组肿瘤植入空白粒子;分别于1周、2周、4周和8周测量肿瘤的大小,同时注射18F-FDG后Micro PET/CT显像,根据最大标准摄取值(SUVmax)计算肿瘤/肌肉摄取比,2个月后处死小鼠,常规HE染色后观察肿瘤细胞形态。结果荷瘤鼠植入125I粒子后1 ~ 2周,18F-FDG PET/CT显像表明,治疗组肿瘤/肌肉与对照组无区别(t= 1.813, P= 0.0721),此时两组肿瘤体积区别不大(t= 1.271, P= 0.111);治疗后4 ~ 8周, 治疗组的18F-FDG的肿瘤/肌肉及肿瘤大小均低于对照组(P < 0.01);经125I粒子治疗后肿瘤细胞大量细胞凋亡,而对照组细胞形态完整;治疗组和对照组8周生存率均为9/10。结论 125I粒子对A549肿瘤的治疗主要以诱导肿瘤细胞凋亡为主,18F-FDG在125I粒子治疗肿瘤4周后评价疗效。更多还原

【Abstract】 Objective This study aims to evaluate the efficacy of 18F-FDG PET/CT imaging in assessing the tumor response to iodine-125 brachytherapy,and to investigate the mechanism of 125 I seeds effect on tumor.Methods A total of 20 A549 xenografts mice were treated with seeds,one groups(10)were treated with 125 Iseeds,other groups(10)were control seeds.The volume of tumors were measured at 1,2,4,8 weeks with calipers.The 18F-FDG Micro PET/CT imaging was performed at the same time.The tumor to muscle(T/NT)ratio was calculated according to the SUV max.All mice were sacrificed at 2 months,and the tumors were evaluated with HE stained.Results There was no obvious difference between the T/NT of treated group and the control group after 1-2 weeks in 18F-FDG images(t = 1.813,P = 0.0721),nor was there any difference found in the measured volume of tumor(t = 1.271,P = 0.111).The T/NT and the volume of tumor in the treated group,however,were significantly different from the control group at and after 4 weeks(P < 0.01).Large number of tumor cells were found toundergo apoptosis after treated with 125 I seeds,while the tumor cells in the control group were intact.Both groups had a survival rate of 9/10 after 8 weeks.Conclusion The 125 I seeds was found to induce apoptosis to tumor cells.18F-FDG PET imaging can be used to monitor the tumor response after 125 I seeds treated after 4 weeks.更多还原