摘要
目的分析离体水平模拟调强放疗照射鼻咽癌细胞系对其放射生物学的影响。方法模拟调强放疗过程对鼻咽癌细胞系进行脉冲式照射,将处方剂量分为1.8、2.0、2.2、2.5 Gy 4组,每组分别分成1 min之内(1个子野),10 min(10个子野)、20 min(20个子野)、30 min(20个子野)完成。照射后经培养计数大于50个细胞的克隆数,并计算细胞存活率。结果1.8 Gy组、2.0 Gy组、2.2 Gy组及2.5 Gy组分别延长照射时间后细胞存活率无明显规律性变化,且与照射时间无明显相关关系。求得4组实验结果的均数,细胞平均存活率随着照射时间的延长而增加,相关系数r=0.999,P=0.000。相对于1 min的常规放疗,10 min、20 min和30 min的平均细胞生存率分别为1.033、1.081和1.117。结论单次照射后延长照射时间并不能降低放射生物学效应;而多次照射的平均细胞放射生物学效应随着照射时间的延长而下降。
Objective To study the effect of changes in fraction delivery time of intensity modulated radiation therapy （IMRT） by in vitro irradiation of cells of nasopharyngeal carcinoma （CNE-2）. Methods CNE-2 were performed for simulating clinical situations and irradiated with 1.8, 2.0, 2.2, 2.5 Gy/fraction with prolonged intervals in 1, 10, 20, 30 minutes. Each surviving fraction was calculated. Results The effect of prolonging the fraction time for each group was not regulative changed with the fraction time. But for the average of the four groups, the surviving fraction was increased with the prolonging time, and there was a correlate relationship with r=0. 999 and P=0. 000. The experiments showed that 10-, 20-, 30-min prolonged delivery time gave a ratio between surviving fractions of 1. 033, 1. 081 and 1. 117. Conclusion The biological effect of prolonging fraction time at conventional dose/fraction is not changed for once treatment but regulative decreases for times of treatment.
出处
《福建医药杂志》
CAS
2009年第6期78-80,共3页
Fujian Medical Journal
基金
福建省卫生厅青年科研课题资助(2006-1-40)
关键词
鼻咽癌细胞
调强放疗
放射生物学效应
Cells of nasopharyngeal carcinoma
Intensity modulated radiotherapy
Traditional biological effect
