Simulation of the Radiation Field at the University Proton Therapy Dresden (UPTD)

Radiation therapy is one of the most used treatment modalities of cancer. While most patients receive photon-therapy, a growing number of patients are treated with particles, mainly protons. Protons offers a more localised dose deposition compared to photon-therapy. This allows to reduce the dose that is applied by the primary beam to the healthy tissue outside the target volume. At the same time, the use of protons leads to a change in the composition of the radiation field, when compared to photons. For example, the out-of-field dose is dominated by secondary neutrons. Additionally, the radiation quality of protons is a function of energy. Therefore, the biological effect depends not only on the physical dose, but also on the linear energy transfer (LET). The neutron field and the LET, like other scientifically interesting quantities, are challenging to measure experimentally. Hence, a simulation that can reproduce the radiation field of a radiation treatment facility is of great value for the study of various aspects of proton therapy.
This work describes the simulation of the University Proton Therapy Dresden (UPTD) beam delivery system and treatment room.