VARIAN Eclipse治疗计划中PBC和AAA算法在直肠癌调强放疗中的剂量学研究比较  

Study on Dosimetric Difference of Rectal Cancer Intensity-modulated Radiation Using PBC and AAA Algorithm in the VARIAN Eclipse Treatment Planning System

作　　者：褚俊峰[1] 李军[2] 桂龙刚 张西志[2] 张先稳[2] 陈永东 孙新臣 李金凯 CHU Junfeng;LI Jun;GUI Longgang;ZHANG Xizhi;ZHANG Xianwen;CHEN Yongdong;SUN Xinchen;LI Jinkai(Department of Radiotherapy,the People＇s Hospital of Jiangdu,Yangzhou 225200,China;Department of Radiotherapy,the People＇s Hospital of SuBei,Yangzhou 225001,China;Department of Radiotherapy,Hongquan Hospital of Yangzhou,Yangzhou 225200,China;Department of Radiation Oncology,the First Affiliated Hospital,Nanjing Medical University,Nanjing 210029,China)

机构地区：[1]扬州市江都人民医院放疗科,江苏扬州225200 [2]苏北人民医院放疗科,江苏扬州225001 [3]扬州洪泉医院放疗科,江苏扬州225200 [4]南京医科大学第一附属医院放疗科,江苏南京210029

出　　处：《肿瘤基础与临床》2018年第4期311-315,共5页journal of basic and clinical oncology

摘　　要：目的比较VARIAN Eclipse计划系统中笔形束卷积(PBC)和各向异性(AAA)算法在直肠癌调强放疗(IMAT)中的剂量学差异,并进行剂量验证。方法随机选取20例直肠癌放疗患者,并在VARIAN Eclipse系统中分别采用PBC算法和AAA算法设计IMRT治疗计划,并利用PTW 729二维剂量验证系统成相应的验证计划,比较靶区及危及器官(OARs)的剂量学参数差异。结果 2种算法模型下,都能满足临床要求,但两者对靶区和OARs的差异影响是比较明显的。对临床靶区(CTV)和计划靶区(PTV)而言,AAA算法模型下的D2%、D5%、D50%、D95%、D98%、Dmean较PBC算法模型更高(P均<0. 05),且CTV的剂量适形度指数和PTV的剂量均匀性指数更好(P均<0. 05);从保护OARs的角度而言,PBC算法模型条件下的小肠Dmax、脊髓Dmax和膀胱D50%较AAA算法模型更低(P均<0. 05);剂量验证中,对整个计划而言,2种算法模型下的γ通过率均能达到95%,都能达满足临床要求(P> 0. 05)。结论对于基于Eclipse系统的直肠癌IMRT计划而言,AAA算法整体上能获得更好的靶区剂量分布,更有利于肿瘤的治疗,但PBC算法却更能保护OARs,降低放疗不良反应。Objective To compare the dosimetric difference of pencil beam convolution （PBC） algorithm and anisotropic analytical algorithm （AAA） algorithm of Eclipse planning system in intensity=modulated radiation （IMRT） of rectal cancer, and to do the dose verification. Methods Twenty patients with radiotherapy of rectal cancer were randomly selected. The PBC algorithm and AAA algorithm were used to design the treatment plan of IMRT in the Eclipse system. The PTW 729 two-dimensional dose verification system was used to establish the corresponding verification plan, and the target area and organs at risk （OARs） dosimetrie parameters were compared. Results Both the algorithms could meet the clinical requirements, but their effects on target area and OARs were more obvious. For clinical target volume （CTV） and planning target volume （ PTV）, D2% , D5% , D50%, D95%, D98%, and D in the AAA algorithm model were higher than those in the PBC model （ P 〈 0.05 ） , and the dose colfformity of CTV and the dose homogeneity of PTV was better （P 〈 0.05） ; from the perspective of protecting OARs, the intesti- nal D spinal-cord D and bladder D50% under the PBC model conditions were lower than the AAA model （P 〈 0.05） ; in the dose verification, the entire plan was in terms of the two algorithms, the 7-pass rate could reach 95% , which could meet the clinical requirements （P 〉 0.05）. Conclusion For the rectal cancer IMRT plan based on Eclipse system, the AAA algorithm can obtain a better target dose distribution overall, which is more conducive to the treatment of tumors, but the PBC algorithm is more able to protect OARs and reduce the side effects of radiotherapy.

关 键 词：直肠癌 调强放疗 AAA算法 PBC算法 剂量学参数 

分 类 号：R735.37[医药卫生—肿瘤] R730.55[医药卫生—临床医学]