Proposal for a dedicated ion beam facility for cancer therapy.

The Radiologische Universitätsklinik Heidelberg, the Deutsche Krebsforschungszentrum Heidelberg (DKFZ) and the Gesellschaft für Schwerionenforschung Darmstadt (GSI) in cooperation with the Forschungszentrum Rossendorf jointly propose to build a hospital-based ion beam facility for tumour therapy in Heidelberg, Germany. Compared to conventional photon radiation, the use of ion beams in cancer therapy has a number of principal advantages which allow the effective tumour dose to be raised while the surrounding healthy tissue can be spared. The proposed facility is capable of treating some 1,000 patients per year. It centers around a synchrotron of 20 meters in diameter which will provide beams of protons, helium, carbon and oxygen ions with energies between 50 and 430 MeV per nucleon. Three therapy rooms will be available, two equipped with gantry systems for multifield irradiation and one with a fixed horizontal beam. The facility will make use of major innovations made in particle therapy during recent years, amongst them: the intensity-controlled rasterscan technique for a 3D tumour-conformal dose delivery, the in-situ verification of the beam position by positron emission tomography (PET), and the realisation of a biologically optimised treatment planning.
All these new developments were successfully realised and tested within a pilot project for ion beam therapy at the accelerator complex of GSI. Already the first patient treatments performed at the pilot facility demonstrated the realibility and clinical applicability of the newly developed techniques. The proposed facility is thus the next step on the path to establish clinical ion beam therapy in Germany and Europe, including techniques which are presently unique on a world-wide scale.