混合野调强增加调强野比例在乳腺癌保乳术后放疗中的应用研究

Applied research of increasing IMRT part in the h-IMRT radiotherapy technique after breast conserving surgery

目的在乳腺癌保乳术后患者中引进新的混合野调强计划h-IMRT(4∶1),并与3D-CRT、h-IMRT(1∶4)、6f-IMRT放疗技术进行对比。方法选取长江大学附属第一人民医院肿瘤科放疗中心2018年9月至2019年10月收治的保乳术后放疗的左右乳腺癌患者各12例作为研究对象,患者均使用上述4种放疗技术进行计划设计并比较其靶区、危机器官参数及机器跳数和执行时间。结果h-IMRT(1∶4)和6f-IMRT与hIMRT(4∶1)和3D-CRT比较,提高了靶区适型度(P<0.5),h-IMRT(1∶4)和6f-IMRT增加了PTV高剂量区体积(V107%),6f-IMRT增加了病灶位于肺部左侧时心脏V5,病灶位于肺部右侧时心脏V5和心脏平均剂量,还增加了肺部V5及病灶位于右侧时的肺部平均剂量及对侧乳腺V5及乳腺平均剂量。混合野调强h-IMRT(1∶4)和h-IMRT(4∶1)显著降低执行时间,6f-IMRT显著增加治疗跳数。结论在混合野调强中提高调强比例并不能提高计划质量,与本研究的其他3种放疗方式比较,在本放疗中心现有设备条件下,h-IMRT(1∶4)仍是左右乳腺癌患者的首选放疗技术。

Objective To add new radiotherapy technique[h-IMRT(4:1)]for patients after breast conserving surgery and compare with three other techniques[3 D-CRT,h-IMRT(1:4),6 f-IMRT].Methods 12 cases of left and right breast cancer patients who received breast-conserving postoperative radiotherapy from September 2018 to October 2019 from the Oncology Department of the First People’s Hospital Affiliated to Yangtze University as the research subjects.All patients used the above four radiotherapy techniques to plan and compared the target area,crisis organ parameters,machine hops and execution time.Results Compared with h-IMRT(4:1)and 3 D-CRT,h-IMRT(1:4)and 6 f-IMRT improved the fitness of the target area(P<0.5),h-IMRT(1∶4)and 6 f-IMRT increased the volume of the PTV high-dose zone(V107%),6 f-IMRT increased the heart V5 when the lesion was on the left,and the heart V5 and MHD when the lesion was on the right,and increased the lung V5 and the lesion on the right MLD and contralateral breast V5 and Dmean.Mixed field intensity modulation h-IMRT(1:4)and h-IMRT(4:1)significantly reduced the execution time,and 6 f-IMRT significantly increased the number of treatment hops.Conclusion Increasing the IMRT part in h-IMRT technique can not improve plan quality,compared with three other radiotherapy techniques,considering the equipment that we have,h-IMRT(1∶4)is still the best radiotherapy technique for breast conserving surgery that we should choose.