动态调强放疗与三维适形放疗计划在局部晚期非小细胞肺癌中靶区及其周围危及器官受照剂量学差异

Dosimetric differences of dynamic intensity modulated radiation therapy and three-dimensional conformal radiation therapy in irradiated targets and endangered organs in locally advanced non-small cell lung cancer

目的探究动态调强放疗(IMRT)与三维适形放疗(3D-CRT)计划在局部晚期非小细胞肺癌(NSCLC)中靶区及其周围危及器官受照剂量学差异。方法 84例局部晚期NSCLC患者随机分为两组,各42例。研究组采用IMRT治疗计划,对照组采用3D-CRT治疗计划。比较两组靶区剂量[平均剂量、不均匀性指数(HI)、适形指数(CI)]、肺部各剂量参数(平均剂量、V_(30)、V_(20)、V_(10)、V_5)、周围危及器官受照剂量(心脏平均剂量、V_(40)及脊髓平均剂量、最大剂量)。结果两组靶区平均剂量对比差异无统计学意义(P>0.05),研究组靶区HI值低于对照组、CI值高于对照组,差异有统计学意义(P<0.01);研究组肺部平均剂量、V_(20)、V_(30)低于对照组,V_5高于对照组,差异有统计学意义(P<0.05或P<0.01),两组V10对比差异无统计学意义(P>0.05);两组心脏平均剂量、V_(40)、脊髓平均剂量对比差异无统计学意义(P>0.05),研究组脊髓最大剂量低于对照组,差异有统计学意义(P<0.05)。结论较3D-CRT,IMRT可有效提高局部晚期NSCLC靶区均匀性与适形度,减少周围危及器官受照射剂量。

Objective To explore the dosimetric differences between the target and the surrounding endangered organs of the dynamic intensity modulated radiotherapy （IMRT） and 3-dimensional conformal radiotherapy （3D-CRT） in locally advanced non-small cell lung cancer（ NSCLC） . Methods Eighty-four cases of locally advanced NSCLC patients were randomly divided into research group and control group with 42 cases in each group. The research group underwent IMRT treatment procedure and the control group was trea-ted with 3D-CRT treatment plan. The target dose[ mean dose,nonuniformity index（ HI） ,and conformal index（ Cl） ] ,lung dose parame-ters （average dose,V30 ,V20, V10, V5） ,and dose of surrounding endangered organs （ average heart dose,V40 and average spinal dose, the maximum dose） were compared between the two groups. Results There was no significant difference between the target dose of the two groups （ P 〉 0. 05 ）. The HI value of the study group was lower than that of the control group and the Cl value was higher than that of the control group （ P 〈 0. 01）. In the study group, the lung average dose, V20, V30 was lower than those of the control group and V5 was higher than that of control group and the difference was statistically significant （ P 〈0. 05 or P 〈0. 01）. There was no significant difference in V10, in cardiac dose, V40 and spinal cord dose （ P 〉 0. 05 ）. The maximal dose of spinal cord in the study group was lower than that in the control group（P 〈 0. 05 ） . Conclusion Compared to 3D-CRT,IMRT program can effectively improve the local advanced NSCLC target uniformity and conformality, reduce the exposure dose of the surrounding endangered organs and is worth promoting.