背景:当前用于硼中子俘获疗法(BNCT)治疗计划的放射生物学模型,依赖于微剂量测定,未能准确表示BNCT的生物学效应。计算相对生物有效性(RBE)和化合物生物有效性(CBE)的精度在确定BNCT的治疗功效中起着关键作用。因此,本研究的重点是如何提高BNCT生物学效应的准确性。
目的:本研究的目的是提出基于纳米剂量测定法的新辐射生物学模型,以准确评估BNCT的RBE和CBE。
方法:纳米剂量学,根植于电离团簇尺寸分布(ICSD),介绍了一种新颖的方法来表征辐射质量通过有效地描绘RBE通过离子轨道结构在纳米尺度。在先前研究的背景下,本研究为RBE和CBE的纳米级评估提供了一个计算模型。我们使用蒙特卡罗代码TOPAS-nBio建立了DNA染色质纤维的简化模型,以评估ICSD对BNCT的适用性并计算纳米剂量学参数。
结果:我们的研究表明,均质和非均质纳米剂量学参数,以及相应的生物模型系数α和β,以及RBE值,表现出响应于细胞内10B浓度变化的变化。值得注意的是,纳米剂量测定参数M1C2$M_1^{{{\\mathrm{C}}}_2}$有效地捕获了模型系数α和RBE的波动。
结论:我们的模型有助于对BNCT进行纳米级分析,能够预测二次离子和RBE的纳米剂量测定量,CBE,和其他与硼分布相关的基本生物学指标。这一贡献显着提高了RBE计算的精度,并为未来在治疗计划中的应用带来了巨大的希望。
BACKGROUND: The current radiobiological model employed for boron neutron capture therapy (BNCT) treatment planning, which relies on microdosimetry, fails to provide an accurate representation the biological effects of BNCT. The precision in calculating the relative biological effectiveness (RBE) and compound biological effectiveness (CBE) plays a pivotal role in determining the therapeutic efficacy of BNCT. Therefore, this
study focuses on how to improve the accuracy of the biological effects of BNCT.
OBJECTIVE: The purpose of this
study is to propose new radiation biology models based on nanodosimetry to accurately assess
RBE and CBE for BNCT.
METHODS: Nanodosimetry, rooted in ionization cluster size distributions (ICSD), introduces a novel approach to characterize radiation quality by effectively delineating RBE through the ion track structure at the nanoscale. In the context of prior research, this
study presents a computational model for the nanoscale assessment of
RBE and CBE. We establish a simplified model of DNA chromatin fiber using the Monte Carlo code TOPAS-nBio to evaluate the applicability of ICSD to BNCT and compute nanodosimetric parameters.
RESULTS: Our investigation reveals that both homogeneous and heterogeneous nanodosimetric parameters, as well as the corresponding biological model coefficients α and β, along with RBE values, exhibit variations in response to varying intracellular 10B concentrations. Notably, the nanodosimetric parameter M 1 C 2 $M_1^{{{\\mathrm{C}}}_2}$ effectively captures the fluctuations in model coefficients α and RBE.
CONCLUSIONS: Our model facilitates a nanoscale analysis of BNCT, enabling predictions of nanodosimetric quantities for secondary ions as well as RBE, CBE, and other essential biological metrics related to the distribution of boron. This contribution significantly enhances the precision of RBE calculations and holds substantial promise for future applications in treatment planning.