Speaking at the International Conference on Monte Carlo Techniques for Medical Applications

I am very pleased to be presenting work at the International Conference on Monte Carlo Techniques for Medical Applications (MCMA2017), October 15- 18 in Naples, Italy.  I am speaking in the “Monte Carlo applications in microdosimetry” section on Tuesday (full presentation info below).  This is my first time attending this conference, but the research topics are a great match to my interests.

Title: Geant4 Modeling of Targeted Radionuclide Therapy for Brain Metastasis

Nicole Ackerman (1*), Nadia Falzone (2), Liset de la Fuente Rosales (3), Katherine A. Vallis (2) and Mario Bernal (3)

(1) Agnes Scott College, Department of Physics and Astronomy, Decatur, United States

(2) University of Oxford, Department of Oncology, CRUK/MRC Oxford Institute for Radiation Oncology, Oxford, United Kingdom

(3) UNICAMP, Departamento de Física Aplicada, Campinas, Brazil

*presenting author

Many patients with breast cancer develop brain metastases, which are typically treated through whole-brain irradiation. As a potential alternative treatment, targeted radionuclide therapy (TRT) could be delivered early, targeting the areas of the vasculature where tumor cells are penetrating into the brain.  We have developed a Monte Carlo model representing brain vasculature to evaluate and understand a variety of potential therapeutic nuclides: (alpha emitters) Pb-212, At-211, Ac-225, Bi-213, and Tb-149; (beta/Auger electron emitters) Lu-177, Tb-161, I-124, In-111, Y-90, Zr-89, and Ga-67.  The micron-scale dose distributions from all radioactive decay products were modeled in Geant4, as well as eV-scale interactions through the G4DNA models [1].  These interactions were then superimposed on an atomic-scale DNA model [2] to estimate strand break yields.  Some of the alpha emitters have decay chains with multiple daughter nuclei; we investigate the change in dose profiles and biological effectiveness as a function of time. Alpha emitters have higher doses per decay, and the depth-dose profiles fall off less quickly.  The general qualities of the depth-dose profiles are maintained through biologically-relevant variations in vasculature geometry.

[1] Bernal MA, Bordage MC, Brown JMC et al. Track structure modeling in liquid water: A review of the Geant4-DNA very low energy extension of the Geant4 Monte Carlo simulation toolkit. Physica Medica 2015;31:861–874.

[2] Bernal MA, Sikansi D, Cavalcante F, Incerti S, Champion C, Ivanchenko V, Francis Z.. An atomistic geometrical model of the B-DNA configuration for DNA–radiation interaction simulations. Computer Physics Communications 2013;184:2840–2847.