BNCT@ANTHEM dosimetry, beam tailoring, radiobiological modelling for the development of a clinical accelerator-based facility

This thesis, developed in the framework of the ANTHEM project (PNC-PNRR), focuses on the implementation and optimization of a new Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT) facility at the University of Campania "Luigi Vanvitelli". BNCT is a binary radiotherapy that uses the high thermal neutron capture cross-section of Boron-10 (10 B) to deliver highly localized, cell-level destruction of tumours through the production of alpha particles and lithium ions. The work spans three main technical pillars: • Facility design and safety: using Monte Carlo simulations to design radiation shielding for the clinical and accelerator rooms, essential for obtaining construction permits. Two focuses were chosen: the design of the external shielding and the evaluation of ambient dose in the technical room, adjacent to the accelerator for human intervention during beam time. The results allowed the assessment of suitable materials and geometries for the external facility walls and to verify the usability of the technical room even in the most conservative scenario. • Beam optimization: tailoring of the neutron beam for clinical application by redesign of the Beam Shaping Assembly (BSA), considering the geometry and characteristic of the target that produce neutrons. This optimization is based on the guidelines published by IAEA and balances clinical efficacy with engineering constraints. • Radiobiological modelling: Utilizing Geant4 to generate a model of the CIRCE facility of the University of Caserta "Luigi Vanvitelli" for the experimental measurement of biological effects due to separate radiation components of the BNCT field. Decoupling the effects is useful to better understand the dose-effect relation and possible synergistic effects. To this end, Geant4-DNA was also used to simulate biological damage at the DNA level, introducing for the first time an internal radiation source, and considering the experimental boron biodistribution measured in cells.