Disclosed is a method of utilizing deuterons (nuclear particles consisting of a proton and a neutron) for charged particle radiotherapy. Compared with proton therapy, at their maximum treatment depth of 66 mm, 125 MeV deuterons possess 82-85% less beam straggling than protons. This difference enables better protection of radiosensitive critical tissues that may be in contact with a tumor. Alternatively, it enables higher doses to be delivered to the tumor, resulting in better tumor control. The implementation of deuteron therapy interchangeably alongside proton therapy requires minor modifications at modest cost to many existing proton therapy systems and provides a clinically useful hybrid particle therapy facility. A free-standing deuteron therapy facility that employs only deuterons is also described.
