Application of the pre-plan-based 3D-printed guide template in interstitial implantation brachytherapy of cervical cancer
Objective To present a method of modeling 3D-printed guide templates(3DPGTs)strictly based on pre-plans for the interstitial implantation brachytherapy of cervical cancer,and elucidate the advantages of 3DPGTs in the interstitial implantation brachytherapy of cervical cancer.Methods This study retrospectively selected six cases of locally advanced cervical cancer treated with interstitial implantation brachytherapy using 3DPGTs.Based on the CT images of 3DPGTs and pre-plans,the mechanical precision of 3DPGTs was verified through image registration.The dosimetric differences were compared between the 3DPGT treatment plan and the pre-plan/the freehand implantation plan.The dosimetric parameters included the volume and D90 for the high-risk clinical target volume(HR-CTV),and the D2cm3,D1cm3,and D0.1cm3 for the bladder,rectum,intestine,and sigmoid.Results The 3DPGTs modeled using the method strictly based on pre-plans exhibited relatively high mechanical precision,with deviations all below 1 mm.Regarding the D90 of the HR-CTV,the 3DPGT treatment plan resulted in a dose of(713.37±143.26)cGy,reduced by 6.95％(z=-1.98,P＜0.05)compared to the(766.62±145.97)cGy in the pre-plan,and increased by 107.6％(z=-1.89,P＜0.05)compared to the(343.56±188.72)cGy in the freehand implantation plan.For dosimetric parameters of organs at risk(OARs),no statistical differences were observed(P＞0.05)between the 3DPGT treatment plan and the pre-plan/the freehand implantation plan.Conclusions The method of modeling 3DPGTs for cervical cancer proposed in this study demonstrates high accuracy.Hence,the dose for the HR-CTV can be substantially increased under the condition that the OARs are protected from over-irradiation.
3D printingCervical cancerInterstitial implantation brachytherapy
万方数据
