非小细胞肺癌调强放疗与螺旋断层放疗剂量学的比较研究

Dosimetric Comparison between Intensity-modulated Radiotherapy and Helical Tomotherapy for Non-small Cell Lung Cancer

目的比较螺旋断层放射治疗(Tomo Therapy治疗计划系统)和常规加速器静态调强放射治疗(Precise Plan治疗计划系统)非小细胞肺癌(NSCLC)患者的剂量分布特点及差异。方法回顾性分析并设计Tomo Therapy和IMRT治疗计划,计划分别传输至Tomo Therapy治疗计划系统(Tomo组)和Precise Plan治疗计划系统(IMRT组),肿瘤靶区给予70 Gy/33 F照射剂量,临床靶区给予60 Gy/33F照射剂量,正常器官全肺<30%、脊髓<45 Gy、心脏<30%、食管<30%,根据剂量分布、剂量体积直方图(DVH)等指标,比较两组剂量分布特点。结果 Tomo组的GTV放射剂量参数HI(1.047±0.015)cGy、Dmax(7406.2±137.1)cGy,均显著低于IMRT组(P<0.05),Tomo组HI值更接近于1。两组CI、Dmini、Dmean比较差异不显著(P>0.05)。Tomo组的PTV放射剂量参数Dmax(7306.4±151.4)cGy、Dmean(6603.8±143.7)cGy,均显著低于IMRT组(P<0.05),两组的CI、Dmini、HI比较差异不显著(P>0.05)。Tomo组的患侧肺脏放射剂量参数Dmax、Dmini、Dmean值与IMRT组比较具有统计学意义(P<0.05)。Tomo组的健侧肺脏放射剂量参数Dmax、Dmini、值与IMRT组比较具有统计学意义(P<0.05),Dmean值比较差异不显著(P>0.05)。Tomo组的脊髓放射剂量参数Dmean、Dmini值与IMRT组比较具有统计学意义(P<0.05),Dmax值比较差异不显著(P>0.05)。Tomo组的心脏放射剂量参数Dmax、Dmean、Dmini值与IMRT组比较差异均无统计学意义(P>0.05)。Tomo组的食管放射剂量参数Dmini值显著高于IMRT组,差异均有统计学意义(P<0.05),两组患者的Dmax、Dmean值差异不显著(P>0.05)。结论研究表明螺旋断层放射治疗肺癌较常规加速器静态调强放射治疗具有更好的放射均匀性,同时对邻近器官组织的放射性伤害更小。

Objective To compare dose distribution characteristics and differences of helical tomography radiotherapy （ TomoTherapy treatment planning system ） and conventional accelerators static IMRT （ PrecisePlan treatment planning system ） for non-small cell lung cancer （NSCLC） patients.Methods Retrospective analysis and design TomoTherapy and IMRT treat-ment plan ,after the CT image tag target and normal organs were transferred to the TomoTherapy treatment planning system （ Tomo group） and PrecisePlan treatment planning system （IMRT group）,GTV give 70Gy/33F dose,clinical target volume give 60Gy/33F dose,normal organs pneumonectomy 〈30%,spinal cord 〈45Gy,heart 〈30%,esophagus 〈30%,according to the dose distribution ,dose volume histograms （ DVH） and other indicators to compare two dose distribution characteristics .Results GTV radiation dose parameters HI Tomo group 1.047 ±0.015 （cGy）,Dmax 7406.2 ±137.1 （cGy） were significantly lower than the IMRT group （P〈0.05）,HI values closer to 1 Tomo group.Two sets of CI,Dmini,Dmean difference was not significant （P〉0.05）.PTV radiation dose parameters Tomo group Dmax 7306.4 ±151.4 （cGy）,Dmean 6603.8 ±143.7 （cGy） were signifi-cantly lower than the IMRT group （P〈0.05）,two groups of CI,Dmini,HI difference was not significant （P〉0.05）.Ipsilateral lung radiation dose parameters Dmax Tomo group ,Dmini,Dmean value IMRT group difference was statistically significant （ P〈0.05）.Contralateral lung radiation dose parameters Dmax Tomo group ,Dmini,value and IMRT group difference was statistically significant （ P 〈0 .05 ） , Dmean value difference was not significant （ P 〉0 .05 ） .Spinal radiation dose parameters Dmean Tomo＆amp;nbsp;group,Dmini value IMRT group difference was statistically significant （P〈0.05）,Dmax comparison value was not significantly different （P〉0.05）.Heart radiation dose parameters Dmax Tomo group ,Dmean,Dmini value IMRT group difference was not sta-tistically significant （P〉0.05）.Heart radiation dose parameters Dmini value Tomo group was significantly higher than IMRT group differences were statistically significant （P〈0.05）,two groups of patients Dmax,Dmean value of the difference was not significant （P〉0.05）.Conclusion Spiral tomography lung cancer compared with conventional radiotherapy accelerator static IMRT has better uniformity of radiation ,while the adjacent organs radioactive hurt smaller .