Primary study of the relative and compound biological effectiveness model for boron neutron capture therapy based on nanodosimetry

Abstract

BackgroundThe 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.PurposeThe purpose of this study is to propose new radiation biology models based on nanodosimetry to accurately assess RBE and CBE for BNCT.MethodsNanodosimetry, 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.ResultsOur 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 effectively captures the fluctuations in model coefficients α and RBE.ConclusionOur 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.

Ionization Detail Parameters for DNA Damage Evaluation in Charged Particle Radiotherapy: Simulation Study Based on Cell Survival Database

“…This paves the way for much easier and more precise radiation therapy treatment planning with various radiation quantities, for instance, multiple ions. The nanoscale approach based on ionization detail parameters is furthermore an opportunity for boron neutron capture radiation therapy [25], where low-energy lithium ions and alpha particles are the source of complex DNA lesion clusters that are lethal to cells. Further therapy enhancement methods, benefiting from boron [26][27][28][29][30] or gadolinium [31] radiation sensitizers exposed to a neutron radiation field produced by a proton beam in a patient, would greatly benefit from a unified nanoscale physics quantity that considers the radiation effectiveness of different particles in a stochastic way.…”