共面与非共面模板在肺癌^(125)Ⅰ粒子植入治疗中的应用

The Comparison of Treatment Plans Between Coplanar Versus Non-Coplanar Template-Assisted ^(125)Ⅰ Particle Implantation for Lung Cancer

目的基于3D打印共面与非共面模板分别设计肺癌患者的^(125)Ⅰ粒子植入治疗计划,比较两种计划的剂量学差异,为临床使用提供依据。方法选取2018年1月至2023年5月于福建省肿瘤医院进行^(125)Ⅰ粒子植入治疗的25例肺癌患者,均采用近距离放射治疗计划系统设计共面与非共面模板辅助的^(125)Ⅰ粒子植入治疗计划,要求共面与非共面计划的肿瘤靶区(GTV)处方剂量覆盖90%以上的GTV。比较两种计划的插值针数、粒子数及GTV剂量学参数[包括90%和100%GTV体积受照射剂量D_(90%)和D_(100%),100%、150%和200%处方剂量的体积百分比V_(100)、V_(150)和V_(200),适形性指数(CI)、GTV外体积指数(EI)和均匀性指数(HI)]与危及器官(OAR)剂量学参数(患侧肺接受20 Gy的体积百分比V_(20)和平均剂量D_(mean)、脊髓最大受照射剂量D_(max))。结果共面计划的插值针数、粒子数均多于非共面计划,差异均有统计学意义(P<0.05)。两种计划的D_(90%)、D_(100%)、V_(100)、V_(200)、EI和HI比较,差异均无统计学意义(P>0.05);共面计划的V_(150)高于非共面计划,CI低于非共面计划,差异均有统计学意义(P<0.05)。共面计划的患侧肺V_(20)、D_(mean)和脊髓D_(max)均高于非共面计划,但差异均无统计学意义(P>0.05)。结论肺癌患者采用共面与非共面模板辅助^(125)Ⅰ粒子植入治疗均可达到靶区剂量覆盖要求,非共面计划的插值针数、粒子数和剂量适形性等计划参数优于共面计划,重要危及器官的吸收剂量也低于共面计划,但价格较昂贵,故临床需要根据具体情况进行选择。

Objective To design^(125)Ⅰ particle implantation treatment plans for lung cancer patients based on 3D printed coplanar and non-coplanar templates,compare the dosimetric differences between the two plans,and provide a basis for clinical use.Methods With the seletion of 25 lung cancer patients who underwent^(125)Ⅰ particle implantation treatment at Fujian Cancer Hospital from January 2018 to May 2023,the design of a close range radiation therapy planning system with^(125)Ⅰ particle implantation assisted by coplanar and non-coplanar templates was adopted,requiring that the prescription dose of gross target volume(GTV)in both coplanar and non-coplanar plans cover more than 90% of GTV.Interpolating needle counts,particle counts,and GTV dosimetry parameters for both plans[including D_(90%) and D_(100%) with 90% and 100% GTV volume exposure doses,and V_(100),V_(150) and V_(200) with volume percentage of 100%,150% and 200% prescribed dose,the conformance index(CI),GTV external index(EI),and homogeneity index(HI)],the organ at risk(OAR)dosimetry parameters(V_(20) with percentage of volume receiving 20 Gy and mean dose D_(mean),maximum spinal cord exposure dose D_(max))were compared.Results The interpolation needle number and particle number of coplanar plan were higher than those of non-coplanar plan,and the differences were statistically significant(P<0.05).There were no significant differences in D_(90%),D_(100%),V_(100),V_(200),EI and HI between the two plans(P>0.05);The V_(150) of coplanar plans was higher than that of non-coplanar plans,and the CI was lower than that of non-coplanar plans,with statistical significance(P<0.05).The V_(20) and D_(mean) of the affected lung and D_(max) of the spinal cord in the coplanar plans were higher than those in the non-coplanar plans,but the differences were not statistically significant(P>0.05).Conclusion For lung cancer patients,both coplanar and non-coplanar template-assisted ^(125)Ⅰ particles implantation can meet the clinical target dose coverage requirements.The plan parameters such as the number of needles,the number of seeds and dose conformity of the non-coplanar plan are better than those of the coplanar plan,and the absorbed dose of important organs at risk is lower than that of the coplanar plan,but the price is more expensive,so the clinical selection needs to be made according to the specific situation.