In the history of external beam radiotherapy, the trend for a better conformation as well as for a higher biological efficiency has been the driving force for the improvement of clinical results. ...However, these two goals had to be followed with separate types of radiation, i.e. photons and neutrons, and could not be combined. For the first time being, beams of heavy ions like carbon offer the possibility to combine both advantageous properties: better targeting and higher biological efficiency. Particle beams have an inverse depth dose profile, with a maximum dose in the deep seated tumor, a finite range, small lateral scattering, and a drastically increased biological efficiency in the tumor. These properties maximize the deletion effects on tumor cells. In addition, particle beams can be directed precisely in the limit of one or two millimeters, and can be monitored using positron emission tomography (PET) with the same precision. In the following paper the conditions are given that are necessary to translate these properties into clinical routine.
We report on the design and test of a 32-channel VLSI chip based on the analog pipeline memory concept. The charge from a strip of a ionization chamber, is stored as a function of time in a switched ...capacitor array. The cell reading can be done in parallel with the writing.
Towards accurate tumour tracking in lungs Baudet, V.; Villard, P.-F.; Jaillet, F. ...
Proceedings on Seventh International Conference on Information Visualization, 2003. IV 2003,
2003
Conference Proceeding
Open access
Motivated by radiotherapy and hadrontherapy improvement, we consider in a first step the potential of a simple elastic mechanical modelling to simulate lung deformations and motions during ...respiration, towards tumour tracking. Two approaches are presented: one is the finite-element based method and the other is the mass-spring system. For these approaches, we suggest a personalisation based on the measurement of physical and geometrical data for each patient.
Proton and carbon therapies of a human brain were simulated using FLUKA, with particular emphasis on treatment monitoring using the prompt gamma method where activities of the source proton/carbon in ...the patient's body are to be extracted from the positional profile of exit photons. Tissue heterogeneity ranging from hydrogen to zinc was represented in a VIP-Man anthropomorphic voxel phantom. Each photon exiting the head was scored with ancestry attributes such as the particle type of its parent, the originating collision type and site. These data, not accessible via physical detectors, were analysed to characterise the escaping photons, delineating signal from noise according to the gamma origin and scatter history. Combinations of energy, geometry, time and angle filters, aided by raytracing, were studied for the optimal compromise between a sufficiently featured exit profile and a statistically adequate count. These will be put in context with ongoing research in the field; our perspective for the prompt gamma method will be discussed in detail.
Radiobiology with charged particles is being carried out in Italy since several decades, starting with the experiments with protons in Milan. Later, also other groups entered the field, such as those ...in Naples, in Legnaro (LNL) and in Rome. In the last 10-15 years the activities in the field began to grow in a significant way. This happened in concomitance with the involvement of various researchers and Institutions in European and international projects devoted to radiation protection aspects, such as those aimed at elucidating and modelling radiation action mechanisms (EC/EU) and those aimed at radiation protection in space (NASA). A special role has been played since then by the Laboratori Nazionali di Legnaro of the INFN, where a radiobiology facility for low energy light ions was set up and operated in 1985. A formidable stimulus for charged-particle radiobiology was more recently given by the onset of plans for developing hadrontherapy Centres in Italy. The TERA Foundation first, and than the TOP Project at the Istituto Superiore di Sanità, at the same time favoured the spreading in Italy of radiobiology research with charged particles and encouraged co-operation among various groups. The Italian radiobiology community, though relatively small, developed a number of valuable activities with charged particles, mostly at the cellular and molecular levels, that span from mechanisms of radiation action to radiation protection in space and to therapy with charged hadrons. In this article, due to space limitations, we have just been able to list the present activities and to briefly review some research that forms a common background for the various areas. This includes the work on Chinese hamster V79 cells irradiated with light ions at LNL, that provided extensive data on the relationships between radiation quality, molecular damage and cellular effects, and the related work aimed at possible interpretation by mechanistic models. It appears that the multiplicity of objectives does not represent a factor of weakness for the relatively small Italian radiobiology community. Synergistic effects have been found because the basic radiobiology is the same for different areas such as radiation protection and hadrontherapy, and because the expertise and the methods developed for a given purpose may find useful applications in others. Though it is difficult to forecast the future development in Italy of the various areas that will take advantage of charged-particle radiobiology, it is expected that hadrontherapy and space radiation protection together, independently of their relative weight, will be important driving forces for the future development of the field in our Country.
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.
Monte Carlo simulations based on the Geant4 toolkit (version 9.1) were performed to study the emission of secondary prompt gamma-rays produced by nuclear reactions during carbon ion-beam therapy. ...These simulations were performed along with an experimental program and instrumentation developments which aim at designing a prompt gamma-ray device for real-time control of hadrontherapy. The objective of the present study is twofold: firstly, to present the features of the prompt gamma radiation in the case of carbon ion irradiation; secondly, to simulate the experimental setup and to compare measured and simulated counting rates corresponding to various experiments. For each experiment, we found that simulations overestimate prompt gamma-ray detection yields by a factor of 12. Uncertainties in fragmentation cross sections and binary cascade model cannot explain such discrepancies. The so-called "photon evaporation" model is therefore questionable and its modification is currently in progress.
Sixty years ago accelerator pioneer Robert Wilson published the paper in which he proposed using protons for cancer therapy. The introduction of protontherapy has been very slow, but in the last 10 ...years the field is booming and five companies offer turn-key centres. Fully stripped ions leave much more energy in the nuclei of the traversed cells than protons of the same range and are thus effective in controlling radio-resistant tumours which cannot be controlled neither with X-rays nor with protons. Paying particular attention to the European contributions, this contribution shortly reviews the history and the developments of carbon ion therapy, a recent chapter of the “hadrontherapy” which covers also radiotherapy with proton and neutron beams.
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