超近距离辐射效应实验分析  

Primary Study of Radioactive Stent

作　　者：杨仁杰[1] 钱晓军 汪幼梅[3] 

机构地区：[1]北京大学临床肿瘤学院介入治疗科,北京市100036 [2]朝阳医院放射科 [3]中国原子能科学研究院同位素研究所放射源制备应用研究室

出　　处：《中国肿瘤临床》2000年第7期540-543,共4页Chinese Journal of Clinical Oncology

基　　金：国家九五介入医学攻关项目!基金资助 (编号 :96 -90 7-0 3 -0 4)

摘　　要：目的 :　进行60 钴外照射和192 铱低剂量率超近距离照射辐射效应的比较 ,以评估放射性支架的可行性。方法 :选用EC10 9细胞系作为研究对象 ,分别用60 钴外照射和192 铱超近距离照射 ,通过观测集落形成率描绘出辐射效应曲线 ,比较在同等剂量下二者辐射效应的差别。并观察同等累积剂量下 ,不同强度192 铱源照射的辐射效应。用 10 0cGy、40 0cGy照射后的细胞接种于裸鼠股部 ,观察移植瘤生长情况。 结果 :二者辐射效应曲线基本符合二次线性数学模型。在相同累积剂量下 ,60 钴外照射比192 铱超近距离照射杀伤力强。在192 铱源照射相同累积剂量时 ,辐射效应相差不大 ,无显著性差异。观察裸鼠移植瘤生长 ,处死时体积和重量存在差异 ,60 钴比192 铱作用大 ,但不显著。结论 :低剂量率近距离照射与外照射相比 ,具有相似的辐射效应。从疗效角度考虑 ,放射性支架具有将放疗和支架置入姑息疗法结合的可能性 ,为食管癌治疗提供新的治疗方法。Objective:To study dose response irradiated by 192 I r as brachytherapy versus 60 Co as routing radiotherapy,and to evaluate the feasibility of radioactive stent.Method:We studied EC109 cell line exposed under γ-ray from 60 Co and 192 I r.Dose-response curves for clonogenic survival were determined following irradiation at five doses:50、100、200、400、800cGy.We also observe the EC109 cell's clonogenic survival rate under the same total doses,irradiated by 192 Ir at different dose rate(raged from 1.924 to 44.25cGy/h).And cells irradiated at doses of 100、400cGy were implanted to bare mice,observed the size and weight of the implanted tumors when mice were killed at 21days after implanted.The distance of source-target is 5mm irradiated by 192 I rand 75cm by 60 Co. Results:The doseresponse curves fit for the linear guadratic model. Under the same total doses, the results of two irradiation sources got a bit different, the injuries irradiated by 192 I r were not so heavy as those irradiated by 60 Co,the clonogenic survival is higher,and tumors grew larger,no value.While irradiated by 192 I r,under the same total doses,effect show no relationship with dose rate,the total doses makes the point.Conclusion:Irradiation from 5mm by 192 Ir show less effect on EC109 cell line under the same dose compared with irradiation at 75cm by 60 Co.At dose rate range from1.924～44.252cGy/h,effect show no relation with dose rate.We suppose to bind 192 Ir with stent treating esophageal malignant stricture,to give palliative treatment and local control.This will be feasible and curative,but with a long distance to clinic trial for more evidence.

关 键 词：近距离放射疗法 辐射效应 放射性支架 食管癌 

分 类 号：R730.5[医药卫生—肿瘤]