计算网格大小对肝癌放疗剂量学和放射生物学参数的影响研究  

Impact of Calculation Grid Size on Dosimetric and Radiobiological Parameters in Radiotherapy for Hepatic Carcinoma

作　　者：吴哲 庞亚 刘可 明智[1] 王东[1] 陈晓梅[1] 王琳[1] 晏军[1] Wu Zhe;Pang Ya;Liu Ke;Ming Zhi;Wang Dong;Chen Xiaomei;Wang Lin;Yan Jun(Department of Radiation Oncology,Zigong First People's Hospital,Zigong 643000,Sichuan,China;Department of Nursing,Zigong First People's Hospital,Zigong 643000,Sichuan,China)

机构地区：[1]自贡市第一人民医院肿瘤科,四川自贡643000 [2]自贡市第一人民医院护理部,四川自贡643000

出　　处：《肿瘤预防与治疗》2021年第1期83-88,共6页Journal of Cancer Control And Treatment

摘　　要：目的∶探讨不同大小计算网格对肝癌容积旋转调强放疗(volumeti modultedarc therapy,VMAT)剂量学和放射生物学参数的影响。方法∶基于Eclipse v13.6计划系统Acur XB算法对20例原发性肝癌患者做回顾性分析,每位患者先使用默认的0.25cm计算网格大小设计VMAT计划,将计划结果再分别用0.10,0.15,0.20,0.30cm的网格大小计算最终的体积剂量。以0.25cm网格数据为参考,采用配对∶检验比较0.25 cm网格组与其他4种不同计算网格下靶区的D2、Dmean、D98、适形指数(cnfrmity index,CI)、均匀性指数(homogeneity index,HI)以及靶区肿瘤控制概率(umwcontrolprobabilit,TCP)和正常肝的并发症发生概率(normal tisue compicaim pohaliliy,NTCP),结合TCP和NTCP比较无并发症肿瘤控制概率(uncomplicated tumor control probability,UTCP),并比较剂量计算时间。结果∶在剂量学参数方面,与0.25cm计算网格组计划相比较,0.100.15、0.20和0.30cm计算网格组计划得到的靶区D2、D98、CI、HI差异均无统计学意义(P>0.05);Dmean除0.10cm组差异有统计学意义外(P=0.031),其余组差异均无统计学意义(P>0.05);其他网格计划组与0.25 cm组相比健侧肾脏Dmean、脊髓Dmax、胃Dmax、小肠Dmax差异均无统计学意义(P>0.05);患侧肾脏Dmean的0.15cm组、0.20 cm组差异有统计学意义(P=0.043,0.044),其他网格组差异均无统计学意义(P>0.05)。在放射生物学参数方面,与0.25 cm计算网格组计划相比较,除0.10cm网格组外(P=0.026)其他网格组计划TCP差异均无统计学意义(P>0.05);NTCP除0.10,0.15 cm计算网格组外(P=0.044、0.048)其他网格组差异均无统计学意义(P>0.05);UTCP差异均无统计学意义(P>0.05)。0.30cm网格组较0.10cm网格组剂量计算效率提高约10倍。结论∶在肝癌VMAT放疗中,计算网格大小会影响剂量计算的准确性。考虑到剂量学参数和放射生物学参数差异无统计学意义以及计算效率,建议选用默认的0.25cm或者0.30cm计算网格。Objective:To explore the impact of different calculation grid sizes on dosimetric and radiobiological parameters of volumetric modulated arc therapy(VMAT)for liver cancer.Methods:Acuros XB dose clculation algorithm implemented in Eclipse v13.6 was used to rerospectively anlye 20 patients with primary liver cancer.The default ealculation grid sixe(0.25 cm)was first used to design the VMAT plan for each patient,and grid sizes of 0.10 cm,0.15 cm,0.20 cm and 0.30 cm were used to calculate the final volume dose.The paired t-test was used to compare D2,Dmean,D98,confornity index(CI),homogeneity index(HI),tumor eontol proba-bility(TCP),normal tssue complication probability(NTCP)and uncomplicated tumor control probability(UTCP)between the 0.25 cm group and every other group,respectively.And the dose calculation time were also compared.Results:D2,D98,CI,HI in the 0.25 cm group was not significanly diferent from those in 0.10 cm,0.15 cm,0.20 cm and 0.30 cm groups,respectively(P>0.05);Dmean in the 0.25 cm group was not significantly different from that in every otber group,respectively(P>0.05)except for the 0.10 cm group(P=0.031);contralatenal kidney Dmean,spinal cord Dmax,stomach Dmax intestine Dmax in the 0.25 cm group was not significantly diferent from those in every other group,respectively(P>0.05);isilaternal kidney Dmean in the 0.25 cm group was sgnifcanly difrent from hat in the 0.15 cm group(P=0.043)and that in the 0.20 cm group(P=0.044).respetively,and was not signifcanly dfferet from that in other two groups,respectively(P>0.05).TCP in the 0.25 cm group was not sgnifcantly dfferet from thal in every other group,respectively(P>0.05)except for the 0.10 cm group(P=0.026);NTCP in the 0.25 cm group was signifcantly difrent from that in the 0.10 cm group(P=0.044)and that in the 0.15 cm goup(P=0.048),respectively,and was not significantly dif-ferent from that in other two groups,respectively(P>0.05);UTCP in the 0.25 cm group was not signifeantly diferent from that in every other group,respectively(P>0.05).The dose calcu

关 键 词：肝癌 容积旋转调强放疗 计算网格 剂量学 放射生物学 

分 类 号：R735.7[医药卫生—肿瘤] R730.55[医药卫生—临床医学]