食管癌三维适形调强放疗过程中肿瘤区的移位及体积变化对其受照剂量的影响研究  

The influence of displacement and volume change of tumor area on the irradiation dose of esophageal cancer during three-dimensional conformal intensity-modulated radiotherapy

作　　者：张延军[1] 王凯 马瑞 王瑾瑜 魏世鸿[2] 谭子璇 ZHANG Yan-jun;WANG Kai;MA Rui;WANG Jin-yu;WEI Shi-hong;TAN Zi-xuan(Radiotherapy Department,Jiugang Hospital,Jiayuguan 735100,China;Radiotherapy Department,Gansu Provincial Cancer Hospital,Lanzhou 730050,China)

机构地区：[1]甘肃省嘉峪关市酒钢医院放疗科,甘肃嘉峪关735100 [2]甘肃省肿瘤医院放疗科,甘肃兰州730050

出　　处：《实用医院临床杂志》2021年第1期15-19,共5页Practical Journal of Clinical Medicine

基　　金：甘肃省科技厅科技支撑计划项目资助(编号:1604FKCA109);嘉峪关市酒钢集团科研项目基金资助(编号:JGKJXM2020109);甘肃省卫生行业科研计划基金资助(编号:GSWSKY-2015-35)。

摘　　要：目的分析食管癌三维适形调强放疗过程中肿瘤区的移位及体积变化对其受照剂量的影响。方法选择2016年5月至2020年5月收治的食管癌患者43例,均接受三维适形调强放疗,观察三维适形调强放疗期间肿瘤区移位、大体肿瘤靶区(GTV)体积变化,及GTV剂量、临床靶区(CTV)剂量、计划靶区(PTV)剂量及危及器官的受照剂量。结果40、60 Gy时肿瘤区前后移位、左右移位的显著移位率均高于20 Gy,差异有统计学意义(P<0.05)。与首次定位时比较,二次定位时GTV总体积、最大横径、长度较小,GTV D100(100%靶体积所受照剂量)、D95、D90、100%处方剂量的靶区体积(V100)、V95及V90较低;CTV及PTV的D100、D95、D90、V100、V95及V90均较小(P<0.05)。靶区移位相同时,采用调强放疗技术的CTV及PTV的D100、D95、D90、V100、V95及V90均少于采用三维适形放疗技术者(P<0.05)。二次定位的脊髓最大剂量、心脏平均剂量、左肺平均剂量及右肺平均剂量均小于首次定位时(P<0.05)。结论食管癌三维适形调强放疗过程中肿瘤区可能发生移位及体积变化,对于靶区有明显变化及移位发生的病例,尤其是采用调强放疗技术的病例,临床可采用CT二次定位并更改放疗计划、加强放疗全过程的质量控制与质量保证,从而改善肿瘤区域的照射精度、受照剂量,减少危及器官照射剂量。Objective To analyze the influence of the displacement and volume change of tumor area on the irradiation dose of esophageal cancer during three-dimensional conformal intensity-modulated radiotherapy.Methods Forty-three patients with esophageal cancer admitted from March 2016 to March 2020 were selected as the research subjects.All patients received three-dimensional conformal intensity-modulated radiotherapy.Tumor area displacement and changes of gross tumor volume(GTV)as well as doses of GTV,clinical target area(CTV),planned target area(PTV)and organ-threatening were observed during the radiotherapy.Results At 40 Gy and 60 Gy,the significant displacement rates of anterior-posterior displacement and left-right displacement of tumor area were higher than that at 20 Gy(P<0.05).In the second positioning,the total volume,maximum transverse diameter and length of GTV were smaller than those in the first positioning(P<0.05).In the second localization,the D100(100%target volume dose),D95 and D90,and the V100(target volume of 100%prescription dose),V95 and V90 were all less than those in the first localization(P<0.05).In the second localization,the D100,D95,D90,V100,V95,V90 of CTV and PTV were less than those in the first localization(P<0.05).The maximum dose of spinal cord,average dose of heart,average dose of left lung and average dose of right lung for the second localization were all smaller than those for the first localization(P<0.05).Conclusion During three-dimensional conformal intensity-modulated radiotherapy for esophageal cancer,the tumor area may be shifted and changed in volume.For cases with obvious changes and shifts in the target area,CT can be used for secondary positioning and the radiotherapy plan can be changed,and the quality control and quality assurance of the whole radiotherapy process can be strengthened.Thus,the irradiation accuracy and irradiation dose of tumor area can be improved and the irradiation dose of dangerous organs could be reduced.

关 键 词：食管癌三维适形调强放疗 肿瘤区移位 体积变化 受照剂量 

分 类 号：R735[医药卫生—肿瘤]