摘要
目的探讨非小细胞肺癌容积旋转调强放射治疗采用Monaco计划系统中Avoidance功能对剂量学参数的影响。方法随机选择非小细胞肺癌患者26例,其中男性19例,女性7例,年龄35~68岁,中位年龄52岁。将患者的数据传至Monaco计划系统,对每例病例勾画防止射线穿过的结构作为Avoidance保护区域,每例病例按是否采用Avoidance功能进行2种计划设计。采用Avoidance功能为治疗组,未采用Avoidance功能为对照组,优化结果要求满足临床要求。分析比较两组计划物理学参数,即计划设计时间、机器出束剂量、治疗时间;分析比较两组剂量学参数,即靶区的D2%、平均剂量(D_(mean))、均匀性指数(HI)、适形度指数(CI)和双肺的剂量体积比及肺平均剂量(MLD)。结果相对于对照组,治疗组计划设计时间增加了(30±7)min,机器出束剂量增加(652±34)MU,出束时间延长了(127±6)s;D_(mean)变大(P=0.019),D2%变大(P=0.013),HI变差(P=0.010),差异均有统计学意义(P<0.05);健侧肺的V5、V10和MLD骤降(P<0.05),患侧肺的V5及双肺的V5及MLD明显下降(P<0.05),差异均有统计学意义;CI变小(P=0.108),但差异无统计学意义(P>0.05),双肺的V20、V30差异无统计学意义(P>0.05)。结论非小细胞肺癌容积调强放射治疗计划设计中,采用Avoidance功能能使肺低剂量区受照体积锐减,同时减少了肺的D_(mean),靶区的覆盖度和适形度不受影响,但均匀性变差(能满足临床剂量限制),计划设计时间、机器出束剂量和出束时间也相应增加。
Objective To explore effect of dosimetric parameters using Avoidance function of Monaco planning system on volumetric modulated arc therapy in patients with non-small cell lung cancer(NSCLC).Methods A total of 26 patients with NSCLC were randomly enrolled,which included 19 males and 7 females,aged 35-68 years old with medium age of 52 years old.The data of patients were transfer to Monaco planning system,which delineated avoidance protection area to prevent exposure of rays,and 2 planning designs were performed according to whether Avoidance function was used.The treatment group performed Avoidance function,and control group did not adopted Avoidance function.The results of control group were optimized to meet clinical requirements.The physical parameters of planned design time,machine beam dose and treatment time between 2 groups were analyzed and compared.The dosimetric parameter such as target area D2%dose,mean dose(D_(mean)),homogeneity index(HI),conformation index(CI),dose-volume ratio and mean lung dose(MLD)were analyzed between 2 groups.Results Compared with control group,the planned design time was increased(30±7)minutes,machine beam dose increased(652±34)MU,and time prolonged(127±6)seconds,D_(mean) was increased(P=0.019),D2%dose was increased(P=0.013)and HI was poor in treatment group(P=0.010),the differences were statistically significant(P<0.05).In treatment group,V5,V10 and MLD in uninjured lung statistically decreased significantly(P<0.05),V5 of affected lung as well as V5 and MLD of bilateral lung were statistically significantly decreased(P<0.05)than in control group.Though CI was smaller(P=0.108)in treatment group,no statistically significant difference was found between 2 groups(P>0.05).Meantime,there was no significant difference in V20 and V30 of bilateral lung between 2 groups(P>0.05).Conclusion It is demonstrated that in NSCLC volumetric modulated arc therapy plan,the Avoidance function could sharply reduce irradiated volume of low-dose lung area and MLD,without affecting the target area coverage and fitness.However,the uniformity of radiation is worse(meet clinical dose),with increasing planned design time,machine beam dose and beam time.
作者
刘旭红
陈晓
赵永军
LIU Xu-hong;CHEN Xiao;ZHAO Yong-jun(Center of Radiation Therapy,Yunnan Cancer Hospital,Kunming 650118,Yunnan,China;The Third Affiliated Hospital of Kunming Medical University,Kunming 650118,Yunnan,China)
出处
《生物医学工程与临床》
CAS
2021年第1期52-57,共6页
Biomedical Engineering and Clinical Medicine
