基于1.5TMR-linac在线自适应MR引导放疗在肝癌患者中的应用  

Application of online adaptive MR guided radiotherapy based on 1.5TMR-linac in hepatocellular carcinoma

作　　者：刘鑫 王华东 李昊东 马文成 李振江 尹勇 LIU Xin;WANG Hua-dong;LI Hao-dong;MA Wen-cheng;LI Zhen-jiang;YIN Yong(Department of Oncology,Affiliated Hospital of Southwest Medical University,Luzhou646000,China;Department of Radiation Physics,Shandong Cancer Hospital and Institute,Shandong First Medical University and Shandong Academy of Medical Sciences,Jinan250117,China;Department of Graduate,Shandong First Medical University(Shandong Academy of Medical Sciences),Jinan250118,China)

机构地区：[1]西南医科大学附属医院肿瘤科,四川泸州646000 [2]山东省肿瘤防治研究院(山东省肿瘤医院)放射物理技术科,山东第一医科大学(山东省医学科学院),山东济南250117 [3]山东第一医科大学(山东省医学科学院)研究生部,山东济南250118

出　　处：《中华肿瘤防治杂志》2022年第23期1685-1690,共6页Chinese Journal of Cancer Prevention and Treatment

基　　金：国家自然科学基金(82102173)。

摘　　要：目的评估1.5T磁共振引导放疗(MRgRT)在肝癌放射治疗中的应用,制定标准的工作流程,并评估流程的可行性。方法分析2021-04-12-2022-04-18在山东省肿瘤医院使用MRgRT的62例肝肿瘤患者临床资料。其中肝细胞癌31例,肝转移瘤31例;放疗方案:7Gy×9次患者20例,常规分割42例。将疾病部位、放疗方案、使用MRgRT的临床依据、物理计划细节、腹部压力呼吸控制和配准误差等因素进行汇总,并在个体之间进行分层次比较,以确定流程实践模式的可行性和普适性。结果34例(54.8%)患者使用8野调强放射治疗;偏移误差X向量位移为(0.55±0.50)cm,Y向量位移为(0.69±0.44)cm,Z向量位移为(0.34±0.31)cm;总体患者计划靶区(PTV)的均匀性指数(HI)平均值为1.10(1.06~1.62),适形性指数(CI)平均值为0.69(0.04~0.9),所有患者靶区体积平均值为(48.16±62.04)cm3,靶区体积与HI(t=5.923,P=0.286)和CI(t=5.980,P=0.06)差异均无统计学意义。身体质量指数(BMI)与X、Y、Z轴向量摆位误差差异均无统计学意义(tx=-0.973,Px=0.339;ty=0.778,Py=0.443;tz=-1.025,Pz=0.314)。单次剂量(HI:t=2.657,P=0.013;CI:t=-3.073,P=0.005)及分割次数(HI:t=2.285,P=0.035;CI:t=-3.504,P=0.003)均与HI/CI存在相关性,放疗计划中<7Gy组及大分割组(≤9次)中的HI、CI更优。性别、BMI与摆位误差在X、Y、Z轴上差异均无统计学意义,均P>0.05。疗效评估结果显示,病情稳定(SD)率为75.8%,疾病进展(PD)率为21.0%,且总体放疗不良反应轻微,未发现放射性肝炎病例。结论本研究制定了MRgRT在肝肿瘤患者中的工作流程,并表明其工作流程是可行的,为进一步开展肝肿瘤磁共振引导放疗提供了理论基础,具有实践意义。Objective To evaluate the application of 1.5T magnetic resonance guided radiotherapy(MRI-guided radiation therapy,MRgRT)in radiotherapy for hepatocellular carcinoma,establish a standard workflow,and evaluate the feasibility of the process.Methods Totally 62patients with liver tumors who used MRgRT in Shandong Cancer Hospital from 2021-04-12to 2022-04-18were analyzed,including 31cases of hepatocellular carcinoma and 31cases of liver metastasis.Radiotherapy regimen:7Gy×9times in 20cases,conventional fractionation in 42cases,34(54.8%)patients were treated with 8-field intensity modulated radiotherapy.For each patient,the disease location,radiotherapy regimen,clinical basis of using MRgRT,details of physical plan,abdominal pressure and respiratory control and registration error were collected and compared among individuals at different levels to determine the feasibility and universality of the process practice model.Results The offset error of X vector displacement was(0.55±0.50)cm,Y vector was(0.69±0.44)cm,Z vector was(0.34±0.31)cm.The homogeneity index(HI),conformability index(CI)and target volume of total patient planning target area(PTV)were 1.10(1.06-1.62),0.69(0.04-0.9)and(48.16±62.04)cm3,respectively.There was no significant difference in target volume between HI(t=5.923,P=0.286)and CI(t=5.980,P=0.06).There was no significant difference between body mass index(BMI)and upward positioning error of X,Y and Z axis(tx=-0.973,Px=0.339;ty=0.778,Py=0.443;tz=-1.025,Pz=0.314).Single dose(HI:t=2.657,P=0.013;CI:t=-3.073,P=0.005)and fractionation times(HI:t=2.285,P=0.035;CI:t=-3.504,P=0.003)were correlated with HI/CI and HI,and CI were better in<7Gy group and large fractionation group(≤9times).There was no significant difference in gender,BMI and positioning error on X,Y and Z axes.Conclusion This study has developed a workflow for MRgRT in patients with liver tumors and the workflow is feasible,providing a theoretical basis for further MR-guided radiotherapy for liver tumors with practical implications.

关 键 词：肝脏肿瘤 磁共振图像引导放射治疗 磁共振加速器 放射治疗 在线自适应 

分 类 号：R735.7[医药卫生—肿瘤]