XIO优化阶数对宫颈癌术后静态调强放射治疗计划的影响  

Influence of XIO Intensity Levels on Static Intensity Modulated Radiation Therapy Plans After Cervical Cancer Surgery

作　　者：邓娟 刘江[1] 梅国建 谢非[1] Deng Juan;Liu Jiang;Mei Guojian;Xie Fei(Department of Oncology,Deyang People's Hospital,Deyang Sichuan 618000,China)

机构地区：[1]德阳市人民医院肿瘤科,四川德阳618000

出　　处：《医疗装备》2022年第17期11-13,17,共4页Medical Equipment

摘　　要：目的通过比较不同优化阶数的宫颈癌术后静态调强放射治疗(IMRT)计划,统计子野数和治疗时间,分析计划靶区(PTV)和危及器官(OAR)的剂量学参数,选择最优优化阶数。方法选择2019-2020年在医院经病理证实且术后有高危、中危因素的宫颈癌患者10例设计放射治疗计划,PTV处方剂量为50 Gy/25 f;计划设计采用XIO 4.64计划系统,为每例患者设计12个静态IMRT计划,均采用7野均分角度入射,优化阶数分别选择20、17、13、10、9、8、7、6、5、4、3、2,待生成多叶光栅序列后使用子野权重优化工具进行优化,统计总子野数及治疗时间,并通过剂量体积直方图(DVH)评价PTV及OAR的剂量分布。结果随着优化阶数由20降低到5,总子野数由(133.3±15.4)个减少到(67.5±6.1)个(P<0.001),治疗时间由(13.6±1.6)min缩短到(7.7±1.3)min(P<0.05),且PTV及OAR各剂量学参数比较差异均无统计学意义(P>0.05)。结论选择不同优化阶数制作宫颈癌术后静态IMRT计划,当优化阶数降为5时,计划仍可满足临床剂量要求,且子野数明显减少,治疗时间明显缩短。Objective The optimal intensity level value was selected through counting the number of segments and treatment time,analyzing the dosimetry parameters of planning target volume(PTV)and organ at risk(OAR)of static intensity modulated radiation therapy(IMRT)plans of different intensity levels after cervical cancer surgery.Methods Radiation therapy plans were designed for 10 patients who were diagnosed with cervical cancer and accompanied with high and intermediate risk factors after radical surgery in the hospital from 2019 to 2020 and the PTV prescription dose was set as 50 Gy/25 f;XIO 4.64 plan system was used to design treatment plans,12 static IMRT plans were designed for each patient and 7 evenly distributed fixed incidence directions were adopted,the intensity levels were set as 20,17,13,10,9,8,7,6,5,4,3 and 2,all plans were optimized with segment weight optimization tool after generating multi-leaf collimator sequences,the total number of segments and the treatment time were counted,and the dosimetry distribution of PTV and OAR were evaluated by dose-volume histogram(DVH).Results With the intensity level value decreasing from 20 to 5,the total number of segments was decreased from(133.3±15.4)to(67.5±6.1)(P<0.001),the treatment time was decreased from(13.6±1.6)min to(7.7±1.3)min(P<0.05),and there were no statistically significant differences in dosimetry parameters of PTV and OAR(P>0.05).Conclusion In selecting different intensity levels to design static IMRT plans after cervical cancer surgery,when the intensity level is set as 5,the plans could still meet the clinical requirements of dose,meanwhile the total number of segments and the treatment time can be significantly reduced.

关 键 词：宫颈癌术后 调强放射治疗 优化阶数 子野数 治疗时间 

分 类 号：R730.55[医药卫生—肿瘤]