摘要
目的 研究使用质子重离子放疗（离子放疗）治疗近消化道肝癌相对光子放疗的剂量学的优势。方法 选取10例肿块紧邻消化道器官放疗患者。治疗处方为用质子照射计划靶区1（PTV-1）50 Gy （RBE）分25次,然后用碳离子照射计划靶区2（PTV-2）15 Gy （RBE）分5次。采用相同数据和处方制定光子同步加量计划,危及器官限值参照RTOG1201。所有计划在满足危及器官限值前提下进行剂量评估。结果 光子计划PTV-1的95%处方剂量线覆盖V95略好于离子计划[（97.15±4.27）%：（96.25±6.69）%,P=0.049],光子计划PTV-2的V95与离子计划相近[（95.12±3.49）%：（94.60±6.22）%,P=0.277]。离子计划受照组织（Body-PTV-1）积分剂量仅是光子计划的39.9%,肝-GTV平均剂量仅为光子计划的81.8%,胃和十二指肠低剂量照射体积显著低于光子计划。结论 肝-GTV受量是制约放疗靶区总剂量提升的主要因素;当肝内GTV较大时离子相比光子能维持相近靶区覆盖同时显著降低肝-GTV受量。
Objective To investigate the dosimetric advantages of proton and heavy ion radiotherapy （particle radiotherapy） for liver cancer adjacent to gastrointestinal tract. Methods Ten patients with liver cancer adjacent to gastrointestinal tract receiving radiotherapy were recruited in this study. The prescription was first given with 50 Gy （RBE）/25 fractions to planning target volume 1（PTV-1） using proton irradiation,and then administered with 15 Gy （RBE）/5 fractions to PTV-2 using carbon-ion irradiation. A simultaneous integrated boost regime was established using the same variables and prescription. The organ at risk （OAR） constraints were referred to RTOG 1201.All plans were performed for dose evaluation after qualifying the OAR constraints. Results The dose coverage of 95% of the prescribed dose（V95） for PTV-1 from the photon plan （97.15%±4.27%）,slightly better than （96.25±6.69%） from the particle plan （P=0.049）.The V95 of PTV-2 from the particle plan was （94.6%±6.22%）,comparable to （95.12%±3.49%） from the photon plan （P=0.277）.The integral dose of Body-PTV-1 delivered by the particle plan was merely 39.9% of that delivered by the photon plan. The mean liver-GTV dose from the particle plan was only 81.8% of that from the photon plan. The low-dose irradiation to the stomach and duodenum from the particle plan was significantly lower than that from the photon plan. Conclusions The dose to the liver-gross tumor volume （GTV） is the main factor limiting the increase of total dose to the tumors. When the absolute GTV in the liver is relatively large,particle radiotherapy can maintain comparable dose coverage to the tumors as the photon radiotherapy whereas significantly reduce the dose to the liver-GTV.
作者
王巍伟
孙家耀
王征
盛尹祥子
蒋国梁
Kambiz Shahnazi
Wang Weiwei;Sun Jiayao;Wang Zheng;Sheng Yinxiangzi;Jiang Guoliang;Kambiz Shahnazi(Department of Medical Physics,Shanghai Proton and Heavy Ion Center,Shanghai 201321,China;Department of Radiation Oncology,Shanghai Proton and Heavy Ion Center,Shanghai 201321,China)
出处
《中华放射肿瘤学杂志》
CSCD
北大核心
2018年第11期999-1003,共5页
Chinese Journal of Radiation Oncology
基金
上海市科学技术委员会科研项目（15411950105）
关键词
离子放射疗法
光子放射疗法
肝肿瘤
剂量学
Particle radiotherapy
Photon radiotherapy
Liver neoplasm
Dosimetriy Dosimetry
