摘要
目的评价螺旋断层调强放疗(TOMO)设备升级后,能否用5.0cm动态钨门替代2.5cm固定钨门治疗中段食管癌。方法对中国医学科学院北京协和医学院肿瘤医院收治的10例局部晚期根治性中段食管癌患者进行研究。在TOMO计划系统分别设计2.5cm固定钨门(FJ2.5)、2.5cm动态钨门(DJ2.5)和5.0cm动态钨门(DJ5.0)计划。比较3种计划的靶区适形度指数(CI)、均匀性指数(HI)和危及器官(OAR)受量以评价计划质量;比较出束时间和机器跳数以评价效率。结果3种计划的靶区CI和HI均满足临床要求。与DJ5.0计划相比,FJ2.5计划的双肺V5和平均剂量、正常组织V5、V10和平均剂量均增加,差异有统计学意义(t=9.751、4.163、11.840、10.321、3.745,P<0.05),DJ2.5计划的心脏V30、V40、平均剂量和最大剂量、正常组织V20和平均剂量均降低,差异有统计学意义(-2.454、-3.275、-4.192、-6.435、-4.139、-6.431,P<0.05)。与DJ2.5计划相比,FJ2.5计划的双肺V5、V20、V30和平均剂量、心脏V30和平均剂量、脊髓和脊髓计划体积(PRV)最大剂量、正常组织V5、V10、V20和平均剂量均增加,差异有统计学意义(t=8.289、6.142、3.137、8.895、3.597、4.565、3.782、5.429、16.421、12.496、8.286、11.933,P<0.05)。与FJ2.5和DJ2.5计划相比,DJ5.0计划的平均出束时间分别缩短43.9%和42.8%,平均机器跳数分别减少42.8%和43.8%。结论若综合考虑计划质量和执行效率,建议采用5.0cm动态钨门技术用于中段食管癌螺旋断层调强放疗,不但可以有效缩短治疗时间、提高射线利用率,而且与2.5cm固定钨门技术相比双肺和正常组织保护更好。若只考虑计划质量,建议采用2.5cm动态钨门技术,其计划质量好。
Objective To evaluate the feasibility of replacing the fixed jaw 2.5 cm mode with dynamic jaw 5.0 cm for mid-esophageal cancer after the upgrade of helical tomotherapy(TOMO).Methods A total of 10 patients with locally advanced esophageal cancer were planned with radical intent using 2.5 cm fixed jaw(FJ2.5),2.5 cm dynamic jaw(DJ2.5)and 5.0 cm dynamic jaw(DJ 5.0)modes respectively on TOMO.Dose conformity index(CI),dose homogeneity index(HI)and dose to OARs were analyzed to evaluate the plan quality.Treatment time and monitor units were used to assess efficiency.Results CI and HI met clinical requirement for all plans.DJ5.0 plans showed significant improvement over FJ2.5 plans in terms of V5 and mean dose to lungs,the V5,V10 and mean dose to normal tissues(t=9.751,4.163,11.840,10.321,3.745,P<0.05).DJ2.5 plans were superior to DJ5.0 plans in the aspects of the V30,V40 and mean dose to heart,the V20 and mean dose to normal tissues(-2.454,-3.275,-4.192,-6.435,-4.139,-6.431,P<0.05).Compared with DJ2.5 plans,the V5,V20,V30 and mean dose to lungs,the V40 and mean dose to heart,maximum dose to cord and cord PRV,the V5,V10,V20 and mean dose to normal tissues of FJ2.5 plans were worse(t=8.289,6.142,3.137,8.895,3.597,4.565,3.782,5.429,16.421,12.496,8.286,11.933,P<0.05).The beam-on time of DJ5.0 plans was significantly reduced by 43.9%and 42.8%compared with FJ2.5 and DJ2.5 plans respectively,and the machine monitor unit was reduced by 42.8%and 43.8%respectively.Conclusions The dynamic jaw of 5.0 cm technique is recommended for treatment of mid-esophageal cancer for sake of plan quality and efficiency.It does not only shorten the treatment time and improve radiation efficiency compared with fixed and dynamic jaw of 2.5 cm technique,but also provides a dosimetric advantage in terms of lung and normal tissue sparing in comparison with fixed jaw of 2.5 cm.When only improving plan quality is concerned,the dynamic jaw of 2.5 cm technique is more recommendable.
作者
刘志强
胡志辉
戴建荣
Liu Zhiqiang;Hu Zhihui;Dai Jianrong(National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital,Chinese Academy of Medical Sciences and Peking Union Medical College,Beijing 100021,China)
出处
《中华放射医学与防护杂志》
CAS
CSCD
北大核心
2019年第1期63-67,共5页
Chinese Journal of Radiological Medicine and Protection
基金
国家重大研发计划项目(20116YFC0904600).
