A method includes directing an ion beam at a tissue. Ions of the ion beam can include positron emitters, such as carbon-11, nitrogen-13, oxygen-15, and fluorine-17. The ions can ionize at least a portion of the tissue and the positron emitters can irradiate the at least a portion of the tissue. The ion beam may be generated with a cyclotron, a synchrotron, or a particle accelerator. The ion beam may be targeted at the tissue using a stereotactic targeting system, clinical dosimetry system, or a positron emission tomography system such that a delivered energy of the ions peaks throughout a volume of the targeted portion of the tissue. The ions may damage a cell in the tissue, and positrons produced, in vivo, by the positron emitters may combine with electrons to create gamma rays that damage the cell in the course of a combination ion beam therapy and brachytherapy treatment.
