Penetrating ion beams are considered interesting supplements to the types of radiation, mostly electrons and gamma rays, that have dominated in radiation research and radiotherapy during the last decades. Biomedical experimentations and clinical studies ar larger ion accelerators (100-1000 MeV/amu) are therefore undertaken in order to exploit their possible clinical use in cancer therapy. It is concluded that an accelerator that permits effective use of protons (ca. 200 MeV) and deutrons (ca. 50 MeV, for neutron therapy) located in a central hospital would represent a convenient tool for clinical investigations at a larger scale.