Nuclear Reactions That Occur in Human Body During Proton Therapy

The depth dose profile of the proton beam used in tumour treatment saves healthy tissues. Together with high biological effectiveness, proton therapy is a very promising type of tumour radiotherapy. Contrary to X/γ beams, protons may easily induce nuclear reactions leaving radioactive isotopes after irradiation. Measurement of the secondary particles along with the determination of the time during which those nuclei remain in the tissues allows to estimate their impact on the therapeutic effects. Animal tissues (heart, liver, and bone) were irradiated with 60 MeV proton beam with different doses at the AIC-144 cyclotron of the Institute of Nuclear Physics PAS. The produced radionuclides were measured via their decay, allowing to estimate the radioactivity of the studied tissues.