胸段食管癌静态调强放疗双肺受量与靶肺比关系研究  

Relationship between PTV lung ratio and bilateral lung dose for intensity-modulated radiotherapy plans of thoracic esophageal cancer

作　　者：杨军 黄洋洋 董胜楠 秦婷婷[2] 刘宗文[2] YANG Jun;HUANG Yangyang;DONG Shengnan;QIN Tingting;LIU Zongwen(Department of Radiotherapy,Third Affiliated Hospital of Zhengzhou University,Zhengzhou 450052,China;Department of Radiotherapy,Second Affiliated Hospital of Zhengzhou University,Zhengzhou 450014,China;Department of Radiotherapy,Henan Province Hospital of TCM,Zhengzhou 450002,China)

机构地区：[1]郑州大学第三附属医院放疗科,河南郑州450052 [2]郑州大学第二附属医院放疗科,河南郑州450014 [3]河南省中医院放疗科,河南郑州450002

出　　处：《中华肿瘤防治杂志》2023年第3期161-165,173,共6页Chinese Journal of Cancer Prevention and Treatment

基　　金：河南省科技攻关计划(182102310700);河南省卫健委医学科技攻关项目联合共建(LHGJ20210407)。

摘　　要：目的 研究靶肺比与调强放疗双肺评价参数的关系,帮助放疗医生和物理师准确评估处方剂量和双肺剂量限值的制约关系,提高计划质量。方法 回顾性分析在郑州大学第二附属医院2018-01-01-2020-12-03接受放疗的114例胸段食管癌患者病例资料,处方剂量为60 Gy/30次,采用曲线拟合方法,建立治疗计划系统(TPS)中读取的双肺评价参数包括V_(5)、V_(10)、V_(20)、V_(30)、肺平均剂量(MLD)与靶肺比的拟合曲线,研究双肺评价参数与靶肺比的关系。结果 V_(5)、V_(10)、V_(20)、V_(30)和MLD分别与靶肺比拟合为三次方曲线,对应的R2分别为0.486(P<0.001)、0.489(P<0.001)、0.504(P<0.001)、0.567(P<0.001)和0.617(P<0.001);5条曲线中,V_(5)、V_(10)、V_(20)、V_(30)和MLD均随着靶肺比的增加呈现出先增加后减小的趋势,且5条曲线的拐点均出现在靶肺比为0.135左右,这时对应的V_(5)、V_(10)、V_(20)、V_(30)和MLD分别处于65%、43%、32%、13%和16 Gy左右。结论 靶肺比≤0.135,需对双肺所受剂量限值提高要求,靶肺比>0.135,需根据情况调整处方剂量或者修改靶区。对靶肺比临界值的研究可以使医生和物理师做出更好的胸段食管癌计划,最大限度保护双肺。Objective To study the relationship between planning target volume(PTV) lung ratio and bilateral lung evaluation parameters of intensity-modulated radiotherapy(IMRT),and to help oncologists and physicists accurately evaluate the restrictive relationship between prescription dose and bilateral lung dose, and to improve the quality of plans.Methods A retrospective analysis was performed on 114 patients with thoracic esophageal cancer who received radiotherapy from the Second Affiliated Hospital of Zhengzhou University from 2018-01-01 to 2020-12-03.The prescribed dose was 60 Gy/30 f.The bilateral lung evaluation parameters read in the treatment planning system(TPS) included fitting curves of V_(5),V_(10),V_(20),V_(30),mean lung dose(MLD) and PTV lung ratio to study the relationship between bilateral lung evaluation parameters and PTV lung ratio.Results The fitting R~2 of V_(5),V_(10),V_(20),V_(30)and MLD to the PTV lung ratio was 0.486(P<0.001),0.489(P<0.001),0.504(P<0.001),0.567(P<0.001) and 0.617(P<0.001),respectively.Among the five curves, V_(5),V_(10),V_(20),V_(30)and MLD all showed a trend of first increasing and then decreasing with the increase of PTV lung ratio, and the inflection point of the five curves all appeared when the PTV lung ratio was about 0.135.At this time, the corresponding V_(5),V_(10),V_(20),V_(30)and MLD were about 65%,43%,32%,13% and 16 Gy respectively.Conclusions If the PTV lung ratio is ≤0.135,the dose limit for bilateral lung should be smaller;if the PTV lung ratio is >0.135,the prescription dose should be adjusted or the PTV should be modified.The study on the critical value of the PTV lung ratio can enable doctors and physicists to make better plans for thoracic esophageal cancer and protect bilateral lung to the maximum extent.

关 键 词：靶肺比 食管癌 调强计划 双肺受量 拟合曲线 

分 类 号：R735.1[医药卫生—肿瘤]