Fondazione CNAO

Milano, Italy

Fondazione CNAO

Milano, Italy
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Parravicini A.,Fondazione CNAO | Calvi G.M.A.,Fondazione CNAO | Rojatti E.,Fondazione CNAO | Viviani C.,Fondazione CNAO
Journal of Physics: Conference Series | Year: 2017

The paper is about the electrostatic pickup installed in the Medium Energy Beam Transfer (MEBT) line of the CNAO (Centro Nazionale di Adroterapia Oncologica), the Italian facility for oncological hadrontherapy. The MEBT Pickup (PUB) has been designed with the purpose of having a continuous and non-interceptive measurement of the horizontal and vertical beam position, close upstream the injection point in the synchrotron. Detector commissioning, data-analysis algorithm and first year measurements are discussed in the paper. © Published under licence by IOP Publishing Ltd.


PubMed | Fondazione CNAO, Polytechnic of Milan and Mi.am srl
Type: Journal Article | Journal: Radiation protection dosimetry | Year: 2014

In this paper, the evaluation of the dosimetric capability of a detector based on a CR-39 solid-state nuclear track detector coupled to a 1 cm thickness of PMMA radiator was made with the aim of understanding the applicability of this technique to personal and environmental neutron dosimetry. The dosemeter has been exposed to monoenergetic and quasi-monoenergetic neutron beams at PTB in Braunschweig, Germany and at Ithemba Laboratories, in Faure, South Africa, with peak energies ranging from 0.565 to 100 MeV. The results showed a response that is almost independent of the neutron energy in the whole energy range.


PubMed | Instituto Europeo Of Oncologia, Fondazione CNAO and Polytechnic of Milan
Type: Journal Article | Journal: Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB) | Year: 2016

The aim of this work was the commissioning of delivery procedures for the treatment of moving targets in scanning pencil beam hadrontherapy.EBT3 films fixed to the Anzai Respiratory Phantom were exposed to carbon ion scanned homogeneous fields (E=332MeV/u). To evaluate the interplay effect, field size and flatness for 3 different scenarios were compared to static condition: gated irradiation or repainting alone and combination of both. Respiratory signal was provided by Anzai pressure sensor or optical tracking system (OTS). End-exhale phase and 1s gating window were chosen (2.5mm residual motion). Dose measurements were performed using a PinPoint ionization chamber inserted into the Brainlab ET Gating Phantom. A sub-set of tests was also performed using proton beams.The combination of gating technique and repainting (N=5) showed excellent results (6.1% vs 4.3% flatness, identical field size and dose deviation within 1.3%). Treatment delivery time was acceptable. Dose homogeneity for gated irradiation alone was poor. Both Anzai sensor and OTS appeared suitable for providing respiratory signal. Comparisons between protons and carbon ions showed that larger beam spot sizes represent more favorable condition for minimizing motion effect.Results of measurements performed on different phantoms showed that the combination of gating and layered repainting is suitable to treat moving targets using scanning ion beams. Abdominal compression using thermoplastic masks, together with multi-field planning approach and multi-fractionation, have also been assessed as additional strategies to mitigate the effect of patient respiration in the clinical practice.


Marinelli M.,University of Rome Tor Vergata | Prestopino G.,University of Rome Tor Vergata | Verona C.,University of Rome Tor Vergata | Verona-Rinati G.,University of Rome Tor Vergata | And 7 more authors.
Medical Physics | Year: 2015

Purpose: To investigate for the first time the dosimetric properties of a new commercial synthetic diamond detector (PTW microDiamond) in high-energy scanned clinical carbon ion beams generated by a synchrotron at the CNAO facility. Methods: The detector response was evaluated in a water phantom with actively scanned carbon ion beams ranging from 115 to 380 MeV/u (30-250 mm Bragg peak depth in water). Homogeneous square fields of 3×3 and 6×6 cm2 were used. Short- and medium-term (2 months) detector response stability, dependence on beam energy as well as ion type (carbon ions and protons), linearity with dose, and directional and dose-rate dependence were investigated. The depth dose curve of a 280 MeV/u carbon ion beam, scanned over a 3×3 cm2 area, was measured with the microDiamond detector and compared to that measured using a PTW Advanced Markus ionization chamber, and also simulated using FLUKA Monte Carlo code. The detector response in two spread-out-Bragg-peaks (SOBPs), respectively, centered at 9 and 21 cm depths in water and calculated using the treatment planning system (TPS) used at CNAO, was measured. Results: A negligible drift of detector sensitivity within the experimental session was seen, indicating that no detector preirradiation was needed. Short-term response reproducibility around 1% (1 standard deviation) was found. Only 2% maximum variation of microDiamond sensitivity was observed among all the evaluated proton and carbon ion beam energies. The detector response showed a good linear behavior. Detector sensitivity was found to be dose-rate independent, with a variation below 1.3% in the evaluated dose-rate range. A very good agreement between measured and simulated Bragg curves with both microDiamond and Advanced Markus chamber was found, showing a negligible LET dependence of the tested detector. A depth dose curve was also measured by positioning the microDiamond with its main axis oriented orthogonally to the beam direction. A strong distortion in Bragg peak measurement was observed, confirming manufacturer recommendation on avoiding such configuration. Very good results were obtained for SOBP measurements, with a difference below 1% between measured and TPS-calculated doses. The stability of detector sensitivity in the observation period was within the experimental uncertainty. Conclusions: Dosimetric characterization of a PTW microDiamond detector in high-energy scanned carbon ion beams was performed. The results of the present study showed that this detector is suitable for dosimetry of clinical carbon ion beams, with a negligible LET and dose-rate dependence. ©2015 Am. Assoc. Phys. Med.


PubMed | University of Pavia, Fondazione CNAO, National Institute of Nuclear Physics, Italy and Oncology and Radiotherapy Institute
Type: Journal Article | Journal: Medical physics | Year: 2015

To describe the dosimetric commissioning and quality assurance (QA) of the actively scanned proton and carbon ion beams at the Italian National Center for Oncological Hadrontherapy.The laterally integrated depth-dose-distributions (IDDs) were acquired with the PTW Peakfinder, a variable depth water column, equipped with two Bragg peak ionization chambers. fluka Monte Carlo code was used to generate the energy libraries, the IDDs in water, and the fragment spectra for carbon beams. EBT3 films were used for spot size measurements, beam position over the scan field, and homogeneity in 2D-fields. Beam monitor calibration was performed in terms of number of particles per monitor unit using both a Farmer-type and an Advanced Markus ionization chamber. The beam position at the isocenter, beam monitor calibration curve, dose constancy in the center of the spread-out-Bragg-peak, dose homogeneity in 2D-fields, beam energy, spot size, and spot position over the scan field are all checked on a daily basis for both protons and carbon ions and on all beam lines.The simulated IDDs showed an excellent agreement with the measured experimental curves. The measured full width at half maximum (FWHM) of the pencil beam in air at the isocenter was energy-dependent for both particle species: in particular, for protons, the spot size ranged from 0.7 to 2.2 cm. For carbon ions, two sets of spot size are available: FWHM ranged from 0.4 to 0.8 cm (for the smaller spot size) and from 0.8 to 1.1 cm (for the larger one). The spot position was accurate to within 1 mm over the whole 20 20 cm(2) scan field; homogeneity in a uniform squared field was within 5% for both particle types at any energy. QA results exceeding tolerance levels were rarely found. In the reporting period, the machine downtime was around 6%, of which 4.5% was due to planned maintenance shutdowns.After successful dosimetric beam commissioning, quality assurance measurements performed during a 24-month period show very stable beam characteristics, which are therefore suitable for performing safe and accurate patient treatments.


PubMed | University of Rome Tor Vergata, University of Pavia, Fondazione CNAO and National Institute of Nuclear Physics, Italy
Type: Comparative Study | Journal: Medical physics | Year: 2015

To investigate for the first time the dosimetric properties of a new commercial synthetic diamond detector (PTW microDiamond) in high-energy scanned clinical carbon ion beams generated by a synchrotron at the CNAO facility.The detector response was evaluated in a water phantom with actively scanned carbon ion beams ranging from 115 to 380 MeV/u (30-250 mm Bragg peak depth in water). Homogeneous square fields of 3 3 and 6 6 cm(2) were used. Short- and medium-term (2 months) detector response stability, dependence on beam energy as well as ion type (carbon ions and protons), linearity with dose, and directional and dose-rate dependence were investigated. The depth dose curve of a 280 MeV/u carbon ion beam, scanned over a 3 3 cm(2) area, was measured with the microDiamond detector and compared to that measured using a PTW Advanced Markus ionization chamber, and also simulated using fluka Monte Carlo code. The detector response in two spread-out-Bragg-peaks (SOBPs), respectively, centered at 9 and 21 cm depths in water and calculated using the treatment planning system (TPS) used at CNAO, was measured.A negligible drift of detector sensitivity within the experimental session was seen, indicating that no detector preirradiation was needed. Short-term response reproducibility around 1% (1 standard deviation) was found. Only 2% maximum variation of microDiamond sensitivity was observed among all the evaluated proton and carbon ion beam energies. The detector response showed a good linear behavior. Detector sensitivity was found to be dose-rate independent, with a variation below 1.3% in the evaluated dose-rate range. A very good agreement between measured and simulated Bragg curves with both microDiamond and Advanced Markus chamber was found, showing a negligible LET dependence of the tested detector. A depth dose curve was also measured by positioning the microDiamond with its main axis oriented orthogonally to the beam direction. A strong distortion in Bragg peak measurement was observed, confirming manufacturer recommendation on avoiding such configuration. Very good results were obtained for SOBP measurements, with a difference below 1% between measured and TPS-calculated doses. The stability of detector sensitivity in the observation period was within the experimental uncertainty.Dosimetric characterization of a PTW microDiamond detector in high-energy scanned carbon ion beams was performed. The results of the present study showed that this detector is suitable for dosimetry of clinical carbon ion beams, with a negligible LET and dose-rate dependence.


PubMed | Fondazione CNAO, National Institute of Nuclear Physics, Italy and University of Cagliari
Type: | Journal: Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB) | Year: 2017

Pencil beam scanning technique used at CNAO requires beam characteristics to be carefully assessed and periodically checked to guarantee patient safety. This study aimed at characterizing the Lynx detector (IBA Dosimetry) for commissioning and periodic quality assurance (QA) for proton and carbon ion beams, as compared to EBT3 films, currently used for QA checks.The Lynx is a 2-D high-resolution dosimetry system consisting of a scintillating screen coupled with a CCD camera, in a compact light-tight box. The scintillator was preliminarily characterized in terms of short-term stability, linearity with number of particles, image quality and response dependence on iris setting and beam current; Lynx was then systematically tested against EBT3 films. The detector response dependence on radiation LET was also assessed.Preliminary results have shown that Lynx is suitable to be used for commissioning and QA checks for proton and carbon ion scanning beams; the cross-check with EBT3 films showed a good agreement between the two detectors, for both single spot and scanned field measurements. The strong LET dependence of the scintillator due to quenching effect makes Lynx suitable only for relative 2-D dosimetry measurements.Lynx appears as a promising tool for commissioning and periodic QA checks for both protons and carbon ion beams. This detector can be used as an alternative of EBT3 films, allowing real-time measurements and analysis, with a significant time sparing.


Schneider R.A.,Paul Scherrer Institute | Vitolo V.,Fondazione CNAO | Albertini F.,Paul Scherrer Institute | Koch T.,Paul Scherrer Institute | And 5 more authors.
Strahlentherapie und Onkologie | Year: 2013

Purpose: Mesenchymal tumours require high-dose radiation therapy (RT). Small bowel (SB) dose constraints have historically limited dose delivery to paraspinal and retroperitoneal targets. This retrospective study correlated SB dose-volume histograms with side-effects after proton radiation therapy (PT). Patients and methods: Between 1997 and 2008, 31 patients (mean age 52.1 years) underwent spot scanning-based PT for paraspinal/retroperitoneal chordomas (81 %), sarcomas (16 %) and meningiom (3 %). Mean total prescribed dose was 72.3 Gy (relative biologic effectiveness, RBE) delivered in 1.8-2 Gy (RBE) fractions. Mean follow-up was 3.8 years. Based on the pretreatment planning CT, SB dose distributions were reanalysed. Results: Planning target volume (PTV) was defined as gross tumour volume (GTV) plus 5-7 mm margins. Mean PTV was 560.22 cm 3. A mean of 93.2 % of the PTV was covered by at least 90 % of the prescribed dose. SB volumes (cm3) receiving doses of 5, 20, 30, 40, 50, 60, 70, 75 and 80 Gy (RBE) were calculated to give V5, V20, V30, V40, V50, V60, V70, V75 and V80 respectively. In 7/31 patients, PT was accomplished without any significant SB irradiation (V5 = 0). In 24/31 patients, mean maximum dose (Dmax) to SB was 64.1 Gy (RBE). Despite target doses of > 70 Gy (RBE), SB received > 50 and > 60 Gy (RBE) in only 61 and 54 % of patients, respectively. Mean SB volumes (cm3) covered by different dose levels (Gy, RBE) were: V20 (n = 24): 45.1, V50 (n = 19): 17.7, V60 (n = 17): 7.6 and V70 (n = 12): 2.4. No acute toxicity ≥ grade 2 or late SB sequelae were observed. Conclusion: Small noncircumferential volumes of SB tolerated doses in excess of 60 Gy (RBE) without any clinically-significant late adverse effects. This small retrospective study has limited statistical power but encourages further efforts with higher patient numbers to define and establish high-dose threshold models for SB toxicity in modern radiation oncology. © 2013 Springer Heidelberg Berlin.


Rossi S.,Fondazione CNAO
European Physical Journal Plus | Year: 2011

The CNAO (Italian acronym that stands for National Centre for Oncological Hadrontherapy) has been realised in Pavia, Italy. It is a clinical facility created and financed by the Italian Ministry of Health and conceived to supply hadrontherapy treatments to patients recruited all over the Country. A qualified network of clinical and research institutes, the CNAO Collaboration, has been created to build and to run the centre. This organizational model turned out to be very efficient and fruitful to reach the goal of introducing the most advanced techniques and procedures of hadrontherapy. Three treatment rooms with four beam ports (three horizontal and one vertical) are operational and one experimental room has been built. Beams of protons with kinetic energies up to 250 MeV and beams of carbon ions with maximum kinetic energy of 400MeV/u are transported and delivered by active scanning systems. The machine operation started in 2009 with the commissioning of the high-technology components that form the acceleration chain from the sources to the patient. The dosimetry and radiobiology tests have been completed with proton beams and CNAO obtained the authorisation to start treating patients. Statistics from the Italian Association of Radiotherapists and Oncologists (AIRO) have estimated that more than 3% of the overall Italian radiotherapy annual patients, i.e. more than 3000 new patients per year, would preferably be treated with hadrontherapy, but this number is steadily increasing. Pre-selection criteria are defined on the basis of established clinical protocols and the hospitals and the clinics in the network will address to the CNAO those patients that satisfy the criteria. This paper outlines the project development, the technical aspects of the realisation and commissioning and the clinical issues relevant for the patients treatments at CNAO. © Societa Italiana di Fisica/Springer-Verlag 2011.


Bazzano G.,Fondazione CNAO
IPAC 2010 - 1st International Particle Accelerator Conference | Year: 2010

The National Centre for Oncological Hadrontherapy (CNAO) will be the first Italian facility for the treatment of deep located tumours with proton and carbon ion beams and active scanning technique. The accelerator complex consists of an injection system, a synchrotron and 5 extraction lines. By the end of 2009 the ECR sources, Low Energy Transfer Line (LEBT), RFQ and LINAC where fully commissioned; in December injection and first turns in the synchrotron were also successfully achieved. Full installation of machine and extraction lines was completed in early 2010. The recent advances in the commissioning and performance of the CNAO complex are being reported in this contribution.

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