PROTON BORON CAPTURE THERAPY: DOSE CALCULATIONS AND A POSSIBLE NEW MEASUREMENT

Since a few decades, proton therapy is being widely used for cancer treatment, with minimal dose to healthy tissues and surrounding organs. Recent studies have suggested that the efficacy of proton therapy could be enhanced if natural boron is selectively accumulated in the tumor tissues. Such an increase is attributed to the protonboron fusion reaction that leads to the production of low-energy α-particles (~2.9 MeV), a mechanism that resembles the well-known Boron Neutron Capture Therapy. However, analytical calculations and detailed Monte Carlo simulations with GEANT4, both in a macro- and micro-dosimetry approach, indicate that the effect of the p+11B→3α reaction, at the standard Boron concentration levels (less than 100 ppm), is orders of magnitude lower than the one of the primary proton beam inside the tissues. In an attempt to solve this discrepancy, an experimental campaign will be carried out with a low-energy proton beam at the CNA laboratory, in Seville. In this talk, we present the latest results of detailed calculations and Geant4 simulations of the dose related to PBCT and describe the concept at the basis of the proposed experimental activity on the PBCT efficacy.