Fast Biological Modeling for Voxel-based Heavy Ion Treatment Planning Using the Mechanistic Repair-Misrepair-Fixation Model and Nuclear Fragment Spectra
Fast Biological Modeling for Voxel-based Heavy Ion Treatment Planning Using the Mechanistic Repair-Misrepair-Fixation Model and Nuclear Fragment Spectra
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DOI：
10.1016/j.ijrobp.2015.07.2264
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发表时间：
2015-11-01
影响因子：
7
通讯作者：
Carlson, David J.
中科院分区：
文献类型：
--
作者：
Kamp, Florian;Cabal, Gonzalo;Carlson, David J.
目的：重离子和光子之间的物理和生物差异尚未得到充分利用，可以改善治疗效果。在碳离子治疗中，治疗计划必须考虑物理性质，如吸收剂量和核碎裂，以及离子与光子相比的相对生物有效性（RBE）的差异。我们结合的mechanistic repairmisrepair-fixation（RMF）模型与蒙特卡洛产生的碎片光谱的生物优化的碳离子treatment plannes.Methods和Materials：双链断裂产量和放射敏感性参数与粒子类型和能量的相对变化进行了测定，使用独立的基准蒙特卡洛损伤模拟和RMF模型估计的RBE值为初级碳离子和二级碎片。深度依赖的能谱产生与临床相关的初始碳离子能量的蒙特卡罗代码FLUKA。RBE的预测趋势与已发表的实验数据进行了比较。生物优化的碳离子实施在一个三维的研究治疗planning tool.Results：我们比较了RBE和RBE加权剂量（RWD）分布的不同的碳离子治疗方案，有和没有核碎片。在模拟中包含碎片导致较小的RBE预测。根据已发表研究中报告的测量细胞存活数据对RMF进行验证，结果显示合理一致。我们计算并优化了患者数据的RWD分布，并将RMF预测与其他生物模型的预测进行了比较。在星形细胞瘤肿瘤的RBE值范围为2.2至4.9（平均2.8）的RWD为3戈伊（RBE）假设（α/β）（X）= 2戈伊。结论：这些研究提供了新的信息，量化和评估的不确定性的临床相关的RBE值的碳离子治疗的生物物理机制的基础上。我们目前的结果，从第一个生物优化的碳离子放射治疗束的患者数据使用相结合的RMF和蒙特卡罗损伤模拟建模方法。所提出的方法有利于快速生物优化。(C)2015 Elsevier Inc. All rights reserved.
Purpose: The physical and biological differences between heavy ions and photons have not been fully exploited and could improve treatment outcomes. In carbon ion therapy, treatment planning must account for physical properties, such as the absorbed dose and nuclear fragmentation, and for differences in the relative biological effectiveness (RBE) of ions compared with photons. We combined the mechanistic repairmisrepair-fixation (RMF) model with Monte Carlo-generated fragmentation spectra for biological optimization of carbon ion treatment plans.Methods and Materials: Relative changes in double-strand break yields and radiosensitivity parameters with particle type and energy were determined using the independently benchmarked Monte Carlo damage simulation and the RMF model to estimate the RBE values for primary carbon ions and secondary fragments. Depth-dependent energy spectra were generated with the Monte Carlo code FLUKA for clinically relevant initial carbon ion energies. The predicted trends in RBE were compared with the published experimental data. Biological optimization for carbon ions was implemented in a 3-dimensional research treatment planning tool.Results: We compared the RBE and RBE-weighted dose (RWD) distributions of different carbon ion treatment scenarios with and without nuclear fragments. The inclusion of fragments in the simulations led to smaller RBE predictions. A validation of RMF against measured cell survival data reported in published studies showed reasonable agreement. We calculated and optimized the RWD distributions on patient data and compared the RMF predictions with those from other biological models. The RBE values in an astrocytoma tumor ranged from 2.2 to 4.9 (mean 2.8) for a RWD of 3 Gy(RBE) assuming (alpha/beta)(X) = 2 Gy.Conclusions: These studies provide new information to quantify and assess uncertainties in the clinically relevant RBE values for carbon ion therapy based on biophysical mechanisms. We present results from the first biological optimization of carbon ion radiation therapy beams on patient data using a combined RMF and Monte Carlo damage simulation modeling approach. The presented method is advantageous for fast biological optimization. (C) 2015 Elsevier Inc. All rights reserved.