Dosimetric assessment of CT-guided radioactive seed implantation assisted by 3D printing non-coplanar template in treatment of chest malignant tumor

目的 对比3D打印模板辅助放射性粒子植入治疗胸部恶性肿瘤的术前、术后计划的剂量学结果,探讨该技术对放射性粒子植入治疗精确性的影响.方法 2016年接受3D打印模板辅助CT引导放射性125I粒子植入胸部肿瘤患者共21例,处方剂量110~180 Gy.患者行术前计划设计、个体化模板制作、穿刺及植入粒子,术后实际剂量学结果与术前计划进行比较,评估参数包括GTV的D90、MPD、V100、V150、CI、EI、HI以及脊髓和胸主动脉D2cc、患侧肺Dmean和V20.采用Wilcoxon非参数相关样本检验.结果 设计并制作3D打印模板共21块.入组患者GTV平均体积为77.1 cm3,平均植入粒子68颗,术后GTV平均D90为147.3 Gy.各剂量学参数术后较术前略有变化,但差异均无统计学意义(P>0.05).结论 3D打印模板技术应用于胸部肿瘤的放射性粒子植入定位准确,术后与术前计划的剂量学一致性良好,提示3D打印模板应用于该部位有良好的治疗精确性.Objective To compare the preoperative and postoperative dosimetric results of radioactive seed implantation assisted by 3D printing template in the treatment of chest malignant tumor, and to examine the effect this technique on the precision of radioactive seed implantation.Methods A total of 21 patients who received 3D printing template-assisted CT-guided 125I seed implantation for chest tumors in 2016 were included in the study.The prescribed dose of the treatment was 110-180 Gy.Preoperative planning, individual template production, and puncture and seed implantation were performed in all patients, and the postoperative dosimetric results were then compared with the preoperative plan by assessing various dosimetric parameters including D90, MPD, V100, V150, CI, EI, and HI of gross tumor volume (GTV), D2cc of the spinal cord and aorta, and Dmean and V20 of the affected side of the lung.Statistical analysis was performed using the Wilcoxon non-parametric test.Results A total of 21 3D printing templates were designed and produced.The mean GTV volume (preoperative) of all patients was 77.1 cm3, and the mean number of implanted seeds was 68.In addition, the mean D90 of the postoperative GTV was 147.3 Gy.There were slight changes in the dosimetric parameters after treatment (P>0.05).Conclusions 3D printing template allows for accurate positioning and implantation of radioactive seeds during the treatment of chest tumor.Postoperative dosimetric parameters were consistent with those in the preoperative planning, indicating that the 3D printing template provides high precision for the treatment of chest tumor.首都临床特色应用研究项目(Z151100004015171) Capital Featured Clinical Application Research Projects中国科学引文数据库(CSCD)7754-7582