目的 比较Monaco计划系统4种通量平滑度对食管癌放疗计划的影响.方法 选取我院23例食管癌患者为研究对象,按照计划靶区 50 Gy/25次的处方剂量,分别使用4种通量平滑模式(Off、Low、Medium和High)设计4组放疗计划,将处方剂量归一至95%的靶区体积后,统计各评价指标,并使用基于等效均匀剂量的参数化正常组织并发症概率(Normal Tissue Complication Probability,NTCP)模型进行评估.使用SPSS 27.0软件进行单因素方差分析,比较各组之间的差异,并使用优劣解距离法(Technique for Order Preference by Similarity to Ideal Solution,TOPSIS)进行综合评估.结果 4组计划在靶区剂量(D98、D2、Dmean、适形度指数、均匀性指数)、危及器官剂量(双肺V30、V20、V10、V5、Dmean、NTCP;心脏V30、Dmean、NTCP;脊髓Dmax)以及计划执行时间和计划总控制点数目方面差异均无统计学意义(P>0.05),在治疗机器跳数(Monitor Units,MU)方面差异显著(P＜0.05),且随着通量平滑程度增加,MU呈降低趋势.TOPSIS综合分析结果显示LOW组综合评分最高.结论 在食管癌放疗计划设计中,4种通量平滑模式均能满足临床治疗要求,通量平滑度的提高可降低治疗MU;考虑计划整体指标的情况下,可选择Low模式达到最优的剂量结果.
Effect of Fluence Smoothing on Radiotherapy Planning for Esophageal Cancer
Objective To compare the effects of four fluence smoothing levels of the Monaco planning system on radiotherapy planning for esophageal cancer.Methods A total of 23 patients with esophageal cancer in our hospital were selected,and four groups of radiotherapy plans were designed using four fluence smoothing modes(Off,Low,Medium and High)according to the prescribed dose of planning target volume 50 Gy/25 fractions.After the prescribed dose was normalized to 95%of the target volume,the evaluation indexes were counted,and the model of parameterized normal tissue complication probability(NTCP)based on equivalent uniform dose was used to evaluated the indexes.The differences between the groups were compared using one-way anova with SPSS 27.0 software,and comprehensive evaluation was made by using the technique for order preference by similarity to ideal solution(TOPSIS).Results There were no statistically significant differences between the four groups in terms of target area dose(D98,D2,Dmean,conformity index,homogeneity index),organs at risk dose(V30,V20,V10,V5,Dmean and NTCP in the lungs;V30,Dmean and NTCP in the heart;Dmax in the spinal cord),as well as the treatment plan deliver time and the total number of planned control points(P＞0.05).There was a significant difference in the planned monitor units(MU)(P＜0.05),which tended to decrease with increasing fluence smoothing.The results of TOPSIS comprehensive analysis showed that the LOW group had the highest comprehensive score.Conclusion In the design of radiotherapy plan for esophageal cancer,all four fluence smoothing modes can meet the clinical treatment requirements,and the increase of fluence smoothing can reduce the treatment MU;considering the overall index of the plan,the Low mode can be selected to achieve the optimal dose results.
esophageal cancerradiotherapy planMonaco planning systemfluence smoothingnormal tissue complication probability
国家科技期刊平台
NSTL
万方数据
维普
