摘要
目的 探讨乳腺癌根治术后减少呼吸运动影响、改善靶区剂量分布、尽可能降低心肺受量放疗计划的设计方法.方法 选择12例乳腺癌根治术后患者,处方剂量为50 Gy,2Gy/次,5次/周.用治疗计划系统分别设计4野调强放疗（4FIMRT）治疗计划和2野适形放疗加4野调强放疗（2FCRT＋4FIMRT）混合治疗计划,比较两种计划的靶区适形度指数（CI）、均匀性指数（HI）、危及器官的受照剂量体积.结果 2FCRT＋ 4FIMRT计划的HI为1.08±0.01,优于4FIMRT计划的1.11±0.01 （P＜0.05）;2FCRT＋ 4FIMRT计划的CI为0.74±0.08,低于4FIMRT计划的0.80±0.03（P＜ 0.05）.2FCRT＋ 4FIMRT计划的同侧肺受照剂量体积V5、V10、平均剂量（Dmean）低于4FIMRT计划,同侧肺V5、V10、Dmean分别较4FIMRT计划降低了13％、23％、7％（均P＜0.05）.2FCRT＋ 4FIMRT计划的对侧肺Dmean、心脏Dmean、对侧乳腺Dmean及V5均低于4FIMRT计划,差异均具有统计学意义（均P＜ 0.05）.两种计划同侧肺V20、V30、心脏V30差异无统计学意义（P＞0.05）.结论 混合照射方式理论上减少了呼吸运动对靶区的影响,提高了靶区剂量的均匀性,降低了乳腺癌放疗并发症的发生风险。
Objective To study how to design the treatment plan to reduce the influence of respiratory movement and the dose of heart and lung as few as possible,to improve the dosage distribution in the target area after radical mastectomy of breast cancer.Methods Twelve patients with breast cancer after radical mastectomy were selected.A dose of 50 Gy with 2 Gy every day and 5 times per week was prescribed.Based on the treatment planning system （TPS）,4-field intensity modulated radiotherapy （4FIMRT） and hybrid intensity modulated treatment planning 2-field conformal radiotherapy （2FCRT） ＋ 4FIMRT were designed respectively.The two plans were compared from the aspects of target conformity index （CI）,the homogeneity index （HI） and exposure dose volume delivered to organ at risk.Results According to the hybrid plan of 2FCRT ＋ 4FIMRT,HI was 1.08±0.01,which was superior to that from 4FIMRT （1.11±0.01,t =9.587,P 〈 0.05）.While CI was 0.74±0.08,based on the plan of 2FCRT＋4FIMRT,which was slightly lower than that from 4FIMRT （0.80±0.03,t =2.497,P 〈 0.05）.Considering the dose volumes on ipsilateral lung in two plans,the values of V5,V10,Dmean of 2FCRT＋4FIMRT plan were significantly less than those of 4FIMRT plan.V5,V10,Dmean from the former plan were 13 %,23 %,7 % less than those from the latter plan （t =6.002,P 〈 0.05;t =6.826,P 〈 0.05;t =3.645,P 〈 0.05）.Meanwhile,Dmean of contralateral lung,Dmean of heart,Dmean and V5 of contralateral breast from the 2FCRT ＋4FIMRT plan were all lower than those of 4FIMRT plan.Those differences between two plans were statistically significant （P 〈 0.05）.Differences of V20 and V30 of ipsilateral lung,and V30 of heart between two plans did not make sense by the statistics analysis （P 〉 0.05）.Conclusion Hybrid radiotherapy theoretically reduces the influence of respiratory movement,improves the uniformity of target dose and lowers the risk of complications of radiation therapy on breast cancer.
出处
《肿瘤研究与临床》
CAS
2015年第8期543-546,共4页
Cancer Research and Clinic
