The Italian hadrontherapy project CNAO.

In 1991 INFN was first involved in R&D work in the field of hadrontherapy. In 1992 the TERA Foundation was created with the purpose of forming and employing people fully devoted to the design, promotion and construction of hadrontherapy centres in Italy and in Europe. This contribution reviews the present status of therapy with ion beams and describes the main TERA project CNAO (Centro Nazionale di Adroterapia Oncologica) based on the optimised medical synchrotron designed in the framework of the "Proton Ion Medical Machine Study" (PIMMS) carried out at CERN from 1996 to 1999 with CERN, the Med-AUSTRO project, GSI, Oncology 2000 (Prague) and TERA as partners.

Hadrontherapy in the world and the programmes of the TERA Foundation.

Hadrontherapy was born in 1938, when neutron beams were used in cancer therapy, but it has become an accepted therapeutical modality only in the last five years. Fast neutrons are still in use, even if their limitations are now apparent. Charged hadron beams are more favorable, since the largest specific energy deposition occurs at the end of their range in matter. The most used hadrons are at present protons and carbon ions. Both allow a dose deposition which conforms to the tumour target. Radiobiological experiments and the results of the first clinical trials indicate that carbon ions have, on top of this macroscopic property, a different way of interacting with cells at the microscopic level. There are thus solid hopes to use carbon beams of about 4500 MeV to control tumours which are radioresistant both to X-rays and protons. After discussing these macroscopic and microscopic properties of hadrontherapy, the hospital-based facilities, running or under construction, are reviewed. The conclusion is that, while in USA and Japan twelve of these centres will be running around the year 2001, in Europe very little is foreseen to use hadrontherapy to treat deep-seated tumours. The most advanced programme is the Italian one, which is described in the last Sections of the report. The main activities concern the construction, near Milano, of a centre for protons and carbon ions called CNAO (National Centre for Oncological Hadrontherapy) and the development of new type of proton accelerators. The Istituto Superiore di Sanita in Rome obtained the initial financing for constructing, in collaboration with ENEA, a 3 GHz linac, which eventually will accelerate protons to 200 MeV, so as to allow deep protontherapy. These, and other hadrontherapy centres in Italy and Europe, will be connected with oncology centres, hospitals and clinics by a multimedial network called RITA, so that before referral each patient's case can be discussed directly by doctors, even located far away, with the experts sitting in the hadrontherapy centres.

Conformal radiation therapy with hadron beams and the programs of the TERA Foundation.

Proposed fifty years ago, tumor therapy with charged hadron beams has been under rapid development since 1993-94. Indeed hadrontherapy was born in 1938, when neutron beams have been used in cancer therapy, but it has become an accepted therapeutical modality only in the last five years. Fast neutrons are still in use, even if their limitations are now apparent. Charged hadron beams are more favorable, since the largest specific energy deposition occurs at the end of their range in matter. The most used hadrons are at present protons and carbon ions. Both allow a dose deposition which conforms to the tumor target. Radiobiology experiments and the results of the first clinical trials indicate that carbon ions have, on top of this macroscopic property, a different way of interacting with cells at the microscopic level. There are thus solid hopes to use carbon beams of about 4500 MeV to control tumors which are radioresistant both to X-rays and protons. After discussing these macroscopic and microscopic properties of hadrontherapy, the twelve dedicated hadrontherapy centres, which will be treating patients from 2001-2002, are shortly described. Five of them are in the USA and seven in Japan, while no hospital based centre for deep protontherapy is fully financed in Europe. The second part of this review is devoted to the Italian hadrontherapy programme, based on the development of the network RITA, the construction in Rome by the "Istituto Superiore di Sanità" of a novel proton accelerator based on a 3 GHz linac, the design of a linac to boost the energy of protons extracted from a 50-70 MeV cyclotron and the construction in Mirasole, near Milano, of a center for protons and ions known as "CNAO". This center will have a synchrotron, which is under design at CERN in the framework of a collaboration of TERA with AUSTRON and GSI which is called PIMMS (Proton Ion Medical Machine Study) and is headed by Dr. Phyl Bryant.

[The hadron therapy project]. / Ii progetto adroterapia.

The neologism "hadrontherapy" means radiotherapy with hadrons, which are the particles constituted by quarks, such as protons, neutrons and ions. The theoretical considerations about the clinical advantages this treatment modality can yield and the results obtained at the centers where it has already been used justify the proposal to project a center of this kind also in our Country. To this purpose, two of the authors of this paper (U. Amaldi, G. Tosi) founded the TERA Group formed by physicists, engineers and radiotherapists who work in close collaboration on a feasibility study for a hadrontherapy facility. The first aim of the Hadrontherapy Project is to design a center equipped with a synchrotron which, at the beginning, will accelerate negative hydrogen ions (H-) which will first produce 70-250 MeV proton beams and, then accelerate light ions (up to 16O) to 430 MeV/amu. This accelerator will serve four or five treatment rooms where patients can be irradiated simultaneously. Two rooms will be equipped with a fixed horizontal beam for the treatment of eye, head and neck tumors; the others will be equipped with rotating gantries to administer, in any clinical situation, really adequate treatment. Such a unit, when enough experience is fained, will allow at least 1000 patients to be treated yearly. The synchrotron injector will be designed so as to allow, parallel to the radiotherapy activities, other applications of medical and biological interest such as: the production of radioisotopes for diagnostic use (especially positron emitters), the analysis of trace elements through the PIXE technique and the production of thermal and epithermal neutrons for boron neutron capture therapy.