基于Monaco系统的宫颈癌伴腹主动脉旁淋巴结转移两种调强计划设计方式的剂量学研究  

Dosimetric research of multiple intensity-modulated radiation therapy planning methods for cervical cancer with para-aortic lymph node metastasis based on the Monaco system

作　　者：戴翔 沈小舟 杨艳[1] 吕圣兰 张丝雨 武雅琴[2] DAI Xiang;SHEN Xiaozhou;YANG Yan;LYU Shenglan;ZHANG Siyu;WU Yaqin(Department of Radiation Oncology,Nanjing Medical University Affiliated Taizhou People's Hospital,Taizhou 225300,China;Department of Radiation Oncology,Nanjing Medical University Affiliated Cancer Hospital,Nanjing 210029,China)

机构地区：[1]南京医科大学附属泰州人民医院放疗科,江苏泰州225300 [2]南京医科大学附属肿瘤医院放疗科,江苏南京210029

出　　处：《大连医科大学学报》2024年第6期518-522,527,共6页Journal of Dalian Medical University

基　　金：2021年度江苏省妇幼健康科研资助项目(F202165)。

摘　　要：目的研究宫颈癌伴腹主动脉旁淋巴结(PALN)转移两种调强计划设计方式的靶区及危及器官(OAR)剂量学特点,为晚期宫颈癌放疗患者的计划设计提供参考。方法选择15例经确诊的宫颈癌伴PALN转移的放射治疗患者,年龄31~79岁。采用Monaco计划系统,全局处方剂量均为50 Gy,对每个病例使用Monaco计划系统在同一CT定位图像上进行容积调强放射治疗(VMAT)、动态多叶光栅调强放疗(DMLCIMRT)两种方式设计放疗计划。比较这两种计划设计方法的靶区剂量下降梯度(R50)、靶区适形度指数(CI)、均匀性指数(HI)及主要OAR的受量。结果DMLC-IMRT计划的靶区R50差于VMAT计划[4.391(4.295,4.771)vs 4.049(4.024,4.451),Z=−3.352,P=0.001];CI也差于VMAT计划[0.724(0.693,0.742)vs 0.753(0.742,0.782),Z=−3.408,P=0.001];HI略优于VMAT计划[0.043(0.042,0.045)vs 0.047(0.043,0.049),Z=−2.707,P=0.007]。DMLC-IMRT计划在肾脏平均剂量(D_(mean))方面低于VMAT[左肾:9.31(8.46,9.84)Gy vs 9.36(9.08,10.28)Gy,Z=−2.726,P=0.006;右肾:9.16(8.92,9.79)Gy vs 9.64(9.04,10.28)Gy,Z=−2.556,P=0.011]。结论两种计划方式均能满足常规治疗的需要。在宫颈癌伴PALN转移的调强放疗中,DMLC-IMRT计划方式可少量降低肾脏D_(mean),但VMAT方法可以得到良好的R50、靶区适形度,从而减少大多数OAR的受量,拥有更高的放疗增益比。Objective To investigate the dosimetric characteristics of two intensity-modulated radiation therapy(IMRT)planning techniques,volumetric modulated arc therapy(VMAT)and dynamic multi-leaf collimator IMRT(DMLC-IMRT)in the treatment of cervical cancer with para-aortic lymph node(PALN)metastasis,in order to provide a reference for the radiotherapy planning of advanced cervical cancer patients.Methods Fifteen patients with confirmed cervical cancer and PALN metastasis were selected,aged between 31 and 79 years.All patients underwent radiation treatment with a prescribed dose of 50 Gy using the Monaco planning system.For each case,treatment plans were designed using both VMAT and DMLC-IMRT on the same CT image set.The dosimetric parameters,including the gradient of the target volume,the conformity index(CI),the homogeneity index(HI),and the dose received by the main organs at risk(OARs)were compared between the two techniques Results The DMLC-IMRT plan showed worse dose gradient[4.391(4.295,4.771)vs 4.049(4.024,4.451),Z=−3.352,P=0.001],95%CI[0.724(0.693,0.742)vs 0.753(0.742,0.782),Z=−3.408,P=0.001],and better HI[0.043(0.042,0.045)vs 0.047(0.043,0.049),Z=−2.707,P=0.007]compared to VMAT.The DMLC-IMRT plan resulted in a lower average dose to the kidneys compared to VMAT[left kidney 9.31(8.46,9.84)Gy vs 9.36(9.08,10.28)Gy,Z=−2.726,P=0.006.right kidney 9.16(8.92,9.79)Gy vs 9.64(9.04,10.28)Gy,Z=−2.556,P=0.011].Conclusion Both planning techniques can meet the requirements for conventional treatment.However,compared to DMLC-IMRT,the VMAT technique provides better dose distribution with a favorable dose gradient and target volume conformity,and reduces the dose to most organs at risk,resulting in a higher therapeutic benefit.

关 键 词：宫颈癌 调强放疗 腹主动脉旁淋巴结转移 计划设计 剂量梯度 

分 类 号：R815.2[医药卫生—放射医学]