单发脑转移性癌IMRT与3D-CRT剂量学对比分析  

Dosimetric Comparison Analysis of IMRT and 3D-CRT in Single Brain Metastasis Carcinoma

作　　者：刘振[1] 张军宁[1] 

机构地区：[1]苏州大学第一附属医院,215000

出　　处：《实用癌症杂志》2016年第8期1345-1348,共4页The Practical Journal of Cancer

摘　　要：目的探讨调强放疗(IMRT)用于单发脑转移性癌治疗的可行性,并评价其相较于三维适形放疗(3DCRT)是否具有剂量学优势。方法取10例单发脑转移性癌患者行体位固定、CT扫描及靶区勾画,分别对每例患者行三维适形放疗(全脑2野对穿+3野局部加量)及5野调强放疗(IMRT)计划设计,分析两种放疗计划的剂量体积直方图,比较两种放疗计划的靶区适形度、均匀指数,靶区剂量、靶区覆盖情况及各个危及器官的受照射剂量。结果 IMRT计划与3D-CRT计划相比显著提高了PTV-G和PTV-C的适形指数(P<0.05),而在靶区均匀指数(HI)方面,IMRT计划与3D-CRT计划未表现出统计学差异(P>0.05)。对于危及器官,IMRT计划显著降低了脑干、视交叉和脑垂体的最大受照射剂量(P<0.05)。结论对于单发脑转移性癌,IMRT和3D-CRT两种计划均能满足合适的靶区覆盖率,均能达到放射治疗的要求,IMRT计划相对于3D-CRT计划有更好的靶区适形性。IMRT计划还可以降低脑干、视交叉和脑垂体的受照射剂量。Objective To evaluate the feasibility of intensity modulated radiation therapy（1MRT） ,and dosimetry advan- tages among IMRT and three dimensional eonformal radiation therapy（3D-CRT）. Methods 10 patients with single brain metas- tases carcinoma received position fix, CT scan and target area sketch, then designed the three dimensional conformal radiation therapy （2 fields for the whole brain ＋ 3 fields as a boost treatment for the GTV） and 5 fields intensity modulated radiation thera- py（IMRT）. The dose volume histograms （DVH） of the 2 radiotherapy plans and 2 radiotherapy plans with conformal target, uni- formity index,target area dose, target area coverage and endanger organ dose were compared. Results Compared with the 3D- C RT, IMRT significantly improved the conformal index（P 〈 0.05 ） of both PTV-G and PTV-C. Both IMRT plan and 3 D-CRT plan showed no statistical difference（ P 〉 0.05 ）. For the organs at risk, 1MRT plan can significantly reduce the maximum irradiation dose of brain stem,optic chiasma and pituitary （P 〈 0.05 ）. Conclusion IMRT and 3 D-CRT can achieve the appropriate target area coverage, can meet the requirements of radiation therapy. For single brain metastases carcinoma, IMRT plan can guarantee a better target dose distribution than 3D-CRT plan. Moreover,IMRT plan can significantly reduce the maximum irradiation dose of brain stem, optic chiasma and pituitary.

关 键 词：单发脑转移性癌 调强放疗 三维适形放疗 剂量分布 

分 类 号：R739.41[医药卫生—肿瘤]