Designing a treatment room dedicated to Boron Neutron Capture Therapy (BNCT) based on a particle accelerator

S. GIROLA; A.A. VALDA; D.M. MINSKY; A.J. KREINER; G. SÁNCHEZ; M.E. CAPOULAT

San Martín, Provincia de Buenos Aires

Congreso; XII Argentinean Meeting of Medical Physics, I Meeting of Medical Physics of the Americas & I AATMN Meeting of Nuclear Medicine and Diagnostic Imaging; 2014

Sociedad Argentina de Física Medica - Universidad de San Martín

Congreso en 2014, artículo en 2015 Introduction: The "Boron Neutron Capture Therapy " (BNCT) is a therapy based on neutron capture reactions that generate selective damage in the 10B diseased tissue, using as Capturer. To the present the implementation of this technique was based on the use of existing nuclear reactors in nuclear research centers. However, these facilities are not suitable to be installed in hospitals or clinics for safety reasons. For the BNCT technique to eventually become a widespread option for treating some forms of cancer or other medical conditions, it is necessary to have a neutron source based on particle accelerators (AB) due to their significant lower cost and complexity. Objectives: This work undertakes the design of an irradiation room for AB-BNCT ready to receive a neutron beam with a high component of epithermal and thermal neutrons through a port (Beam Shaping Assembly or BSA) connecting the treatment room with the accelerators. Materials and Methods: This work is based on the development of the shielding for the BSA and the geometry of the treatment room. The materials were selected based on their nuclear properties, to minimize the residual background radiation that occurs during the treatment due to unwanted interactions of neutrons with matter. The shielding of the treatment room was defined to ensure compliance with current regulations in Argentina in radiation protection for occupationally exposed workers and members of the public. This work consists of two parts, one experimental and one based on numerical simulations using the Monte Carlo method. Results: We estimated, in various sectors outside the treatment room, using numerical simulations, the dose rates contributed by neutrons: thermal, epithermal and fast and photons generated by neutron reactions with matter. Conclusions: The treatment room is able to accept a neutron beam with therapeutic properties and shield the secondary radiation produced primarily by interaction of neutrons with matter. Simulations show that the total dose rate at the outside of the treatment room is in the order of magnitude of the design constraint for the public and significantly below the restriction to workers. This design should be subjected to optimization, after the establishment of the final site and working conditions, this additional information will allow us to reduce the proposed dimensions. Keywords: Radiotherapy, BNCT, Shielding, Neutron