Dinkla Anna M, van der Laarse Rob, Kaljouw Emmie, Pieters Bradley R, Koedooder Kees, van Wieringen Niek, Bel Arjan
Department of Radiation Oncology, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands.
Department of Radiation Oncology, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands.
Brachytherapy. 2015 Mar-Apr;14(2):279-88. doi: 10.1016/j.brachy.2014.09.006. Epub 2014 Oct 22.
Graphical optimization (GrO) is a common method for high-dose-rate/pulsed-dose-rate (PDR) prostate brachytherapy treatment planning. New methods performing inverse optimization of the dose distribution have been developed over the past years. The purpose is to compare GrO and two established inverse methods, inverse planning simulated annealing (IPSA) and hybrid inverse treatment planning and optimization (HIPO), and one new method, enhanced geometric optimization-interactive inverse planning (EGO-IIP), in terms of speed and dose-volume histogram (DVH) parameters.
For 26 prostate cancer patients treated with a PDR brachytherapy boost, an experienced treatment planner optimized the dose distributions using four different methods: GrO, IPSA, HIPO, and EGO-IIP. Relevant DVH parameters (prostate-V100%, D90%, V150%; urethra-D(0.1cm3) and D(1.0cm3); rectum-D(0.1cm3) and D(2.0cm3); bladder-D(2.0cm3)) were evaluated and their compliance to the constraints. Treatment planning time was also recorded.
All inverse methods resulted in shorter planning time (mean, 4-6.7 min), as compared with GrO (mean, 7.6 min). In terms of DVH parameters, none of the inverse methods outperformed the others. However, all inverse methods improved on compliance to the planning constraints as compared with GrO. On average, EGO-IIP and GrO resulted in highest D90%, and the IPSA plans resulted in lowest bladder D2.0cm3 and urethra D(1.0cm3).
Inverse planning methods decrease planning time as compared with GrO for PDR/high-dose-rate prostate brachytherapy. DVH parameters are comparable for all methods.
图形优化（GrO）是高剂量率/脉冲剂量率（PDR）前列腺近距离放射治疗治疗计划的常用方法。在过去几年中，已经开发出了对剂量分布进行逆向优化的新方法。目的是在速度和剂量体积直方图（DVH）参数方面比较GrO与两种既定的逆向方法，即逆向计划模拟退火（IPSA）和混合逆向治疗计划与优化（HIPO），以及一种新方法，增强几何优化-交互式逆向计划（EGO-IIP）。
对于26例接受PDR近距离放射治疗强化的前列腺癌患者，一位经验丰富的治疗计划师使用四种不同方法优化剂量分布：GrO、IPSA、HIPO和EGO-IIP。评估了相关的DVH参数（前列腺-V100%、D90%、V150%；尿道-D(0.1cm³)和D(1.0cm³)；直肠-D(0.1cm³)和D(2.0cm³)；膀胱-D(2.0cm³)）及其对约束条件的符合情况。还记录了治疗计划时间。
与GrO（平均7.6分钟）相比，所有逆向方法的计划时间都更短（平均4-6.7分钟）。在DVH参数方面，没有一种逆向方法优于其他方法。然而，与GrO相比，所有逆向方法在对计划约束条件的符合情况方面都有所改善。平均而言，EGO-IIP和GrO导致最高的D90%，而IPSA计划导致最低的膀胱D2.0cm³和尿道D(1.0cm³)。
与GrO相比，逆向计划方法可减少PDR/高剂量率前列腺近距离放射治疗的计划时间。所有方法的DVH参数具有可比性。
