Investigation of photon doses reaching healthy tissues in the use of different neutron energies in boron neutron capture therapy

Abstract

Boron neutron capture therapy is a unique treatment method that aims to kill the tumor cells with the help of heavy particles. Particles resulting from the interaction of the tumor region containing 10B atoms with thermal or epithermal neutrons have the most important role in this treatment method. In this study, gamma radiation reaching healthy tissues, which is the result of 10B(n,a)7Li reaction, was investigated. A simulation suitable for boron neutron capture therapy treatment, including the human head model, was created by the Monte Carlo N-Particle (MCNP) program. By using five different neutron energies, the gamma radiations resulting from the 10B(n,a)7Li reaction in the determined regions, close to the tumor tissue, were investigated. It was observed that the healthy tissue between the tumor area and the surface is exposed to the highest gamma flux and the highest gamma radiation absorption. It was also observed that these values increase as neutron energy decreases. It was found that the gamma doses received by some regions outside the neutron irradiation area could be significant. It has been understood that the change in neutron energy may cause significant changes in gamma radiation values reaching healthy tissues, especially in regions close to the surface. In boron neutron capture therapy treatments, the neutrons sent to the tumor should be selected depending on the location of the tumor and the size of the tumor area. This study contains significant data about photon doses in healthy tissues around the brain region treated using different neutron energies with the boron neutron capture therapy technique.