A peer-reviewed journal published by K. N. Toosi University of Technology

Boron, gadolinium, and lithium neutron capture therapy: A multi-scale simulation by Geant4 and Geant4-DNA toolkits

Document Type : Research Article

Author

Department of Physics and Energy Engineering, Amirkabir University, Tehran, Iran

Abstract
Boron neutron capture therapy (BNCT) is an emerging targeted radiation therapy leveraging nuclear capture reactions to maximize tumor cell destruction with minimal damage to healthy tissues. Given to clinical possible concentrations, attentions have recently been paid to 10B alternatives. This study presents a dosimetric comparison between BNCT, gadolinium neutron capture therapy (GdNCT) and lithium neutron capture therapy (LiNCT) using the Geant4 Monte Carlo toolkit, evaluating dose distributions and therapeutic gain across varying concentrations (1-50 ppm) of 10B, 157Gd, and 6Li in a Snyder head phantom. Furthermore, Geant4-DNA simulations were employed to quantify DNA damage and predict cell survival via the Two-Lesion Kinetic model. The results demonstrate that both BNCT and LiNCT, as alpha-emitters, achieve superior tumor dose enhancement and normal tissue sparing compared to GdNCT. At 50 ppm, BNCT and LiNCT produced a 64-85% dose enhancement, outperforming GdNCT by more than 20-fold. Micro-scale analysis revealed that 10B and 6Li induce a high proportion of complex, lethal DNA double-strand breaks, leading to a steep, concentration-dependent decrease in cell survival. While 6Li is identified as a potent and promising alternative alpha-emitter, 10B maintained a marginally higher biological effectiveness. This study not only confirms BNCT's clinical superiority but also provides a rigorous framework for evaluating novel neutron-capture agents, underscoring the critical importance of radiation quality over neutron cross-section alone.

Highlights

  • BNCT and LiNCT show superior tumor dose over GdNCT.
  • Alpha emitters spare healthy tissue; GdNCT increases OAR dose.
  • B-10 and Li-6 agents induce complex, lethal DNA double-strand breaks.
  • Cell survival decreases steeply with B-10/Li-6 concentration.
  • Radiation quality outweighs cross-section for NCT efficacy.

Keywords


Copyright
RPE is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0).

Conflict of Interest
The authors declare no potential conflict of interest regarding the publication of this work‎.

Funding
‎The authors declare that no funds‎, ‎grants‎, ‎or other financial support were received during the preparation of this manuscript‎.

 
Agostinelli, S., Allison, J., Amako, K. a., et al. (2003). Geant4a simulation toolkit. Nuclear instruments and methods in physics research section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 506(3):250–303.
Allison, J., Amako, K., Apostolakis, J., et al. (2016). Recent developments in Geant4. Nuclear instruments and methods in physics research section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 835:186–225.
Arce, P., Archer, J. W., Arsini, L., et al. (2025). Results of a Geant4 benchmarking study for biomedical applications, performed with the G4-Med system. Medical Physics, 52(5):2707–2761.
Arce, P., Bolst, D., Bordage, M.-C., et al. (2021). Report on G4-Med, a Geant4 benchmarking system for medical physics applications developed by the Geant4 Medical Simulation Benchmarking Group. Medical physics, 48(1):19–56.
Bertolet, A., Ramos-Méndez, J., McNamara, A., et al. (2022). Impact of DNA geometry and scoring on Monte Carlo track-structure simulations of initial radiation-induced damage. Radiation Research, 198(3):207–220.
Brown, D. A., Chadwick, M. B., Capote, R., et al. (2018). ENDF/B-VIII. 0: the 8th major release of the nuclear reaction data library with CIELO-project cross sections, new
standards and thermal scattering data. Nuclear Data Sheets, 148:1–142.
Chatzipapas, K. P., Tran, N. H., Dordevic, M., et al. (2023). Simulation of DNA damage using Geant4-DNA: an overview of the molecularDNA example application. Precision Radiation Oncology, 7(1):4–14.
Chen, Z., Yang, P., Lei, Q., et al. (2019). Comparison of BNCT dosimetry calculations using different GEANT4 physics lists. Radiation Protection Dosimetry, 187(1):88–97.
Deagostino, A., Protti, N., Alberti, D., et al. (2016). Insights into the use of gadolinium and gadolinium/boron-based agents in imaging-guided neutron capture therapy applications. Future Medicinal Chemistry, 8(8):899–917.
Francis, Z., Villagrasa, C., and Clairand, I. (2011). Simulation of DNA damage clustering after proton irradiation using an adapted DBSCAN algorithm. Computer Methods and Programs in Biomedicine, 101(3):265–270.
Goorley, J., Kiger Iii, W., and Zamenhof, R. (2002). Reference dosimetry calculations for neutron capture therapy with comparison of analytical and voxel models. Medical Physics, 29(2):145–156.
Han, Y., Geng, C., Altieri, S., et al. (2023a). Combined BNCT-CIRT treatment planning for glioblastoma using the effect-based optimization. Physics in Medicine & Biology,
69(1):015024.
Han, Y., Geng, C., Liu, Y., et al. (2023b). Calculation of the DNA damage yield and relative biological effectiveness in boron neutron capture therapy via the Monte Carlo track structure simulation. Physics in Medicine & Biology, 68(17):175028.
Ho, S. L., Yue, H., Tegafaw, T., et al. (2022). Gadolinium neutron capture therapy (GdNCT) agents from molecular to nano: Current status and perspectives. ACS Omega, 7(3):2533–2553.
Hosmane, N. S. (2012). Boron and gadolinium neutron capture therapy for cancer treatment. World Scientific.
IAEA. (2023). Advances in boron neutron capture therapy. International Atomic Energy Agency.
Incerti, S., Baldacchino, G., Bernal, M., et al. (2010). The Geant4-DNA project.
International Journal of Modeling, Simulation, and Scientific Computing, 1(02):157–178.
Incerti, S., Kyriakou, I., Bernal, M., et al. (2018). Geant4-DNA example applications for track structure simulations in liquid water: a report from the Geant4-DNA Project. Medical Physics, 45(8):e722–e739.
Ivanyan, V. (2020). The possibility of an appropriate neutron beam achievement for medical purposes based on GEANT4 calculations. The European Physical Journal Plus, 135(1):69.
Jin, W. H., Seldon, C., Butkus, M., et al. (2022). A review of boron neutron capture therapy: its history and current challenges. International Journal of Particle Therapy, 9(1):71–82.
Karamitros, M., Luan, S., Bernal, M. A., et al. (2014). Diffusion-controlled reactions modeling in Geant4-DNA. Journal of Computational Physics, 274:841–882.
Karamitros, M., Mantero, A., Incerti, S., et al. (2011). Modeling radiation chemistry in the Geant4 toolkit. Prog Nucl Sci Technol, 2(0).
Karaoglu, A., Arce, P., Obradors, D., et al. (2018). Calculation by GAMOS/Geant4 simulation of cellular energy distributions from alpha and lithium-7 particles created by BNCT. Applied Radiation and Isotopes, 132:206–211.
Kyriakou, I., Sakata, D., Tran, H. N., et al. (2021). Review of the Geant4-DNA simulation toolkit for radiobiological applications at the cellular and DNA level. Cancers, 14(1):35.
Lampe, N., Karamitros, M., Breton, V., et al. (2018). Mechanistic DNA damage simulations in Geant4-DNA part 1: A parameter study in a simplified geometry. Physica Medica, 48:135–145.
Le, U. M. and Cui, Z. (2006). Biodistribution and tumor-accumulation of gadolinium (Gd) encapsulated in long-circulating liposomes in tumor-bearing mice for potential neutron capture therapy. International Journal of Pharmaceutics, 320(1-2):96–103.
Lee, W., Kim, K. W., Lim, J. E., et al. (2022). In vivo evaluation of the effects of combined boron and gadolinium neutron capture therapy in mouse models. Scientific Reports, 12(1):13360.
Li, L. and Watabe, H. (2025). The effectiveness of combining gadolinium and boron neutron capture therapy at the cellular level. Journal of Nuclear Science and Technology, 62(4):331–340.
Makvandi, M., Dupis, E., Engle, J. W., et al. (2018). Alpha-emitters and targeted alpha therapy in oncology: from basic science to clinical investigations. Targeted oncology, 13(2):189–203.
Meylan, S., Incerti, S., Karamitros, M., et al. (2017). Simulation of early DNA damage after the irradiation of a fibroblast cell nucleus using Geant4-DNA. Scientific Reports, 7(1):11923.
Mitin, V., Kulakov, V., Khokhlov, V., et al. (2009). Comparison of BNCT and GdNCT efficacy in treatment of canine cancer. Applied Radiation and Isotopes, 67(7-8):S299–S301.
Moghaddasi, L. and Bezak, E. (2017). Development of an integrated monte carlo model for glioblastoma multiforme treated with boron neutron capture therapy. Scientific Reports, 7(1):7069.
Moghaddasi, L. and Bezak, E. (2018). Geant4 beam model for boron neutron capture therapy: investigation of neutron dose components. Australasian Physical & Engineering Sciences in Medicine, 41(1):129–141.
Moghaddasi, L. and Bezak, E. (2023). An Integrated Monte Carlo Model for Heterogeneous Glioblastoma Treated with Boron Neutron Capture Therapy. Cancers, 15(5):1550.
Mortazavi, S., Rafiepour, P., Mortazavi, S., et al. (2024). Radium deposition in human brain tissue: A Geant4-DNA Monte Carlo toolkit study. Zeitschrift für Medizinische Physik, 34(1):166–174.
Nikjoo, P. O’Neill, D. G. and M. Terrissol, H. (1997). Computational modelling of low-energy electron-induced DNA damage by early physical and chemical events. International Journal of Radiation Biology, 71(5):467–483.
Pistone, D., Bortolussi, S., Fatemi, S., et al. (2025). A GATE Monte Carlo study on ICRP110 phantoms for BNCT dosimetry evaluation. Applied Radiation and Isotopes, 220:111724.
Rafiepour, P., Sina, S., and Mortazavi, S. M. J. (2022). Inactivation of SARS-CoV-2 by charged particles for future vaccine production applications: a Monte Carlo study. Radiation Physics and Chemistry, 198:110265.
Roots, R., Chatterjee, A., Chang, P., et al. (1985). Characterization of hydroxyl radical-induced damage after sparsely and densely ionizing irradiation. International Journal of Radiation Biology and Related Studies in Physics, Chemistry and Medicine, 47(2):157–166.
Sakata, D., Lampe, N., Karamitros, M., et al. (2019). Evaluation of early radiation DNA damage in a fractal cell nucleus model using Geant4-DNA. Physica Medica, 62:152–157.
Sato, T., Masunaga, S.-i., Kumada, H., et al. (2018). Microdosimetric modeling of biological effectiveness for boron neutron capture therapy considering intra-and intercellular heterogeneity in10B distribution. Scientific Reports, 8(1):988.
Shamsabadi, R. and Baghani, H. R. (2024a). DNA-damage RBE assessment for combined boron and gadolinium neutron capture therapy. Journal of Applied Clinical Medical Physics, 25(7):e14399.
Shamsabadi, R. and Baghani, H. R. (2024b). Impact of gadolinium concentration and cell oxygen levels on radiobiological characteristics of gadolinium neutron capture therapy technique in brain tumor treatment. Radiological Physics and Technology, 17(1):135–142.
Shanmugam, M., Kuthala, N., Kong, X., et al. (2023). Combined gadolinium and boron neutron capture therapies for eradication of head-and-neck tumor using Gd-10 B-6 nanoparticles under MRI/CT image guidance). JACS Au, 3(8):2192–2205.
Shin, W.-G., Sakata, D., Lampe, N., et al. (2021). A Geant4-DNA evaluation of radiation-induced DNA damage on a human fibroblast. Cancers, 13(19):4940.
Snyder, W. S., Ford, M. R., Warner, G. G., et al. (1969). Estimates of absorbed fractions for monoenergetic photon sources uniformly distributed in various organs of a heterogeneous phantom. Technical report, Oak Ridge National Lab., Tenn.
Stewart, R. D. (2001). Two-lesion kinetic model of double-strand break rejoining and cell killing. Radiation research, 156(4):365–378.
Togtokhtur, T., Dushanov, E., Kulahava, T., et al. (2024). Calculation of DNA Damage in the Tumor Cell on Boron Neutron Capture Therapy. Physics of Particles and Nuclei
Letters, 21(4):811–814.
Tran, H. N., Ramos-Méndez, J., Shin, W.-G., et al. (2021). Assessment of DNA damage with an adapted independent reaction time approach implemented in Geant4-DNA for the simulation of diffusion-controlled reactions between radioinduced reactive species and a chromatin fiber. Medical Physics, 48(2):890–901.
Uddin, M., Chowdhury, M., Hossain, S., et al. (2008). Thermal neutron capture cross sections for the 152S(n, γ)153Sm and 154Sm(n, γ)155Sm reactions at 0.0536 eV energy. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 266(22):4855–4861.
Vafapour, H., Rafiepour, P., Moradgholi, J., et al. (2025a). Evaluating the biological impact of shelters on astronaut health during different solar particle events: A Geant4-DNA simulation study. Radiation and Environmental Biophysics, 64(1):137-150.
Vafapour, H., Rafiepour, P., Moradgholi, J., et al. (2025b). Optimizing Dual-layer Neutron Moderators for Accelerator-based Boron Neutron Capture Therapy: A Geant4 Simulation Study. Journal of Medical Physics, 50(3):450–456.
Wang, S., Zhang, Z., Miao, L., et al. (2022). Boron neutron capture therapy: current status and challenges. Frontiers in Oncology, 12:788770.
Wang, Z., Zheng, Q., Wang, B., et al. (2025). Recent research progress of BNCT treatment planning system. Nuclear Engineering and Technology, 57(3):103264.
Zhou, T., Igawa, K., Kasai, T., et al. (2024a). The current status and novel advances of boron neutron capture therapy clinical trials. American Journal of Cancer Research, 14(2):429.
Zhou, Y.-T., Cheng, K., Liu, B., et al. (2024b). Recent progress of nano-drugs in neutron capture therapy. Theranostics, 14(8):3193.
Zolghadri, S., Rafiepour, P., and Yousefnia, H. (2025). Quantifying DNA strand breaks from targeted alpha emitters 225Ac and 227Th via Geant4-DNA: implications for RBE and cell survival. EJNMMI physics, 12(1):92.
 
Volume 7, Issue 1
Winter 2026
Pages 59-70

  • Receive Date 14 October 2025
  • Revise Date 29 November 2025
  • Accept Date 19 December 2025