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McCabe A, Martin S, Rowe S, Shah J, Morgan PS, Borys D, Panek R. Oxygen-enhanced MRI assessment of tumour hypoxia in head and neck cancer is feasible and well tolerated in the clinical setting. Eur Radiol Exp 2024; 8:27. [PMID: 38443722 PMCID: PMC10914657 DOI: 10.1186/s41747-024-00429-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 01/08/2024] [Indexed: 03/07/2024] Open
Abstract
BACKGROUND Tumour hypoxia is a recognised cause of radiotherapy treatment resistance in head and neck squamous cell carcinoma (HNSCC). Current positron emission tomography-based hypoxia imaging techniques are not routinely available in many centres. We investigated if an alternative technique called oxygen-enhanced magnetic resonance imaging (OE-MRI) could be performed in HNSCC. METHODS A volumetric OE-MRI protocol for dynamic T1 relaxation time mapping was implemented on 1.5-T clinical scanners. Participants were scanned breathing room air and during high-flow oxygen administration. Oxygen-induced changes in T1 times (ΔT1) and R2* rates (ΔR2*) were measured in malignant tissue and healthy organs. Unequal variance t-test was used. Patients were surveyed on their experience of the OE-MRI protocol. RESULTS Fifteen patients with HNSCC (median age 59 years, range 38 to 76) and 10 non-HNSCC subjects (median age 46.5 years, range 32 to 62) were scanned; the OE-MRI acquisition took less than 10 min and was well tolerated. Fifteen histologically confirmed primary tumours and 41 malignant nodal masses were identified. Median (range) of ΔT1 times and hypoxic fraction estimates for primary tumours were -3.5% (-7.0 to -0.3%) and 30.7% (6.5 to 78.6%) respectively. Radiotherapy-responsive and radiotherapy-resistant primary tumours had mean estimated hypoxic fractions of 36.8% (95% confidence interval [CI] 17.4 to 56.2%) and 59.0% (95% CI 44.6 to 73.3%), respectively (p = 0.111). CONCLUSIONS We present a well-tolerated implementation of dynamic, volumetric OE-MRI of the head and neck region allowing discernment of differing oxygen responses within biopsy-confirmed HNSCC. TRIAL REGISTRATION ClinicalTrials.gov, NCT04724096 . Registered on 26 January 2021. RELEVANCE STATEMENT MRI of tumour hypoxia in head and neck cancer using routine clinical equipment is feasible and well tolerated and allows estimates of tumour hypoxic fractions in less than ten minutes. KEY POINTS • Oxygen-enhanced MRI (OE-MRI) can estimate tumour hypoxic fractions in ten-minute scanning. • OE-MRI may be incorporable into routine clinical tumour imaging. • OE-MRI has the potential to predict outcomes after radiotherapy treatment.
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Affiliation(s)
- Alastair McCabe
- Academic Unit of Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham, UK.
- Department of Clinical Oncology, Nottingham University Hospitals NHS Trust, City Hospital, Hucknall Road, Nottingham, NG5 1PB, UK.
| | - Stewart Martin
- Academic Unit of Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham, UK
| | - Selene Rowe
- Department of Radiology, Nottingham University Hospitals NHS Trust, Nottingham, UK
| | - Jagrit Shah
- Department of Radiology, Nottingham University Hospitals NHS Trust, Nottingham, UK
| | - Paul S Morgan
- Mental Health & Clinical Neurosciences Unit, School of Medicine, University of Nottingham, Nottingham, UK
- Department of Medical Physics & Clinical Engineering, Nottingham University Hospitals NHS Trust, Nottingham, UK
| | - Damian Borys
- Department of Systems Biology and Engineering, Silesian University of Technology, Gliwice, Poland
| | - Rafal Panek
- Mental Health & Clinical Neurosciences Unit, School of Medicine, University of Nottingham, Nottingham, UK
- Department of Medical Physics & Clinical Engineering, Nottingham University Hospitals NHS Trust, Nottingham, UK
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Qian J, Yu X, Li B, Fei Z, Huang X, Luo P, Zhang L, Zhang Z, Lou J, Wang H. In vivo Monitoring of Oxygen Levels in Human Brain Tumor Between Fractionated Radiotherapy Using Oxygen-enhanced MR Imaging. Curr Med Imaging 2020; 16:427-432. [PMID: 32410542 DOI: 10.2174/1573405614666180925144814] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 08/19/2018] [Accepted: 09/11/2018] [Indexed: 11/22/2022]
Abstract
BACKGROUND It was known that the response of tumor cells to radiation is closely related to tissue oxygen level and fractionated radiotherapy allows reoxygenation of hypoxic tumor cells. Non-invasive mapping of tissue oxygen level may hold great importance in clinic. OBJECTIVE The aim of this study is to evaluate the role of oxygen-enhanced MR imaging in the detection of tissue oxygen levels between fractionated radiotherapy. METHODS A cohort of 10 patients with brain metastasis was recruited. Quantitative oxygen enhanced MR imaging was performed prior to, 30 minutes and 22 hours after first fractionated radiotherapy. RESULTS The ΔR1 (the difference of longitudinal relaxivity between 100% oxygen breathing and air breathing) increased in the ipsilateral tumor site and normal tissue by 242% and 152%, respectively, 30 minutes after first fractionated radiation compared to pre-radiation levels. Significant recovery of ΔR1 in the contralateral normal tissue (p < 0.05) was observed 22 hours compared to 30 minutes after radiation levels. CONCLUSION R1-based oxygen-enhanced MR imaging may provide a sensitive endogenous marker for oxygen changes in the brain tissue between fractionated radiotherapy.
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Affiliation(s)
- Junchao Qian
- Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei Cancer Hospital, Hefei 230031, China.,Anhui Province Key Laboratory of Medical Physics and Technology, Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
| | - Xiang Yu
- Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei Cancer Hospital, Hefei 230031, China
| | - Bingbing Li
- Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei Cancer Hospital, Hefei 230031, China
| | - Zhenle Fei
- Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei Cancer Hospital, Hefei 230031, China
| | - Xiang Huang
- Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei Cancer Hospital, Hefei 230031, China
| | - Peng Luo
- Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei Cancer Hospital, Hefei 230031, China
| | - Liwei Zhang
- Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei Cancer Hospital, Hefei 230031, China
| | - Zhiming Zhang
- Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei Cancer Hospital, Hefei 230031, China
| | - Jianjun Lou
- Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei Cancer Hospital, Hefei 230031, China
| | - Hongzhi Wang
- Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei Cancer Hospital, Hefei 230031, China.,Anhui Province Key Laboratory of Medical Physics and Technology, Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
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Bendinger AL, Seyler L, Saager M, Debus C, Peschke P, Komljenovic D, Debus J, Peter J, Floca RO, Karger CP, Glowa C. Impact of Single Dose Photons and Carbon Ions on Perfusion and Vascular Permeability: A Dynamic Contrast-Enhanced MRI Pilot Study in the Anaplastic Rat Prostate Tumor R3327-AT1. Radiat Res 2019; 193:34-45. [PMID: 31697210 DOI: 10.1667/rr15459.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We collected initial quantitative information on the effects of high-dose carbon (12C) ions compared to photons on vascular damage in anaplastic rat prostate tumors, with the goal of elucidating differences in response to high-LET radiation, using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Syngeneic R3327-AT1 rat prostate tumors received a single dose of either 16 or 37 Gy 12C ions or 37 or 85 Gy 6 MV photons (iso-absorbed and iso-effective doses, respectively). The animals underwent DCE-MRI prior to, and on days 3, 7, 14 and 21 postirradiation. The extended Tofts model was used for pharmacokinetic analysis. At day 21, tumors were dissected and histologically examined. The results of this work showed the following: 1. 12C ions led to stronger vascular changes compared to photons, independent of dose; 2. Tumor growth was comparable for all radiation doses and modalities until day 21; 3. Nonirradiated, rapidly growing control tumors showed a decrease in all pharmacokinetic parameters (area under the curve, Ktrans, ve, vp) over time; 4. 12C-ion-irradiated tumors showed an earlier increase in area under the curve and Ktrans than photon-irradiated tumors; 5. 12C-ion irradiation resulted in more homogeneous parameter maps and histology compared to photons; and 6. 12C-ion irradiation led to an increased microvascular density and decreased proliferation activity in a largely dose-independent manner compared to photons. Postirradiation changes related to 12C ions and photons were detected using DCE-MRI, and correlated with histological parameters in an anaplastic experimental prostate tumor. In summary, this pilot study demonstrated that exposure to 12C ions increased the perfusion and/or permeability faster and led to larger changes in DCE-MRI parameters resulting in increased vessel density and presumably less hypoxia at the end of the observation period when compared to photons. Within this study no differences were found between curative and sub-curative doses in either modality.
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Affiliation(s)
- Alina L Bendinger
- Departments of Medical Physics in Radiology.,Faculty of Biosciences, University of Heidelberg, Heidelberg, Germany
| | - Lisa Seyler
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Germany
| | - Maria Saager
- Departments of Medical Physics in Radiation Oncology.,Heidelberg Institute for Radiation Oncology (HIRO) and National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Charlotte Debus
- Departments of Translational Radiation Oncology, National Center for Tumor Diseases (NCT).,Department of High-Performance Computing, Simulation and Software Technology, German Aerospace Center (DLR), Cologne, Germany
| | - Peter Peschke
- Departments of Medical Physics in Radiation Oncology.,Heidelberg Institute for Radiation Oncology (HIRO) and National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | | | - Jürgen Debus
- Departments of Clinical Cooperation Unit, Radiation Therapy, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO) and National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Department of Radiation Oncology and Radiotherapy, University Hospital Heidelberg, Heidelberg, Germany
| | - Jörg Peter
- Departments of Medical Physics in Radiology
| | - Ralf O Floca
- Departments of Medical Image Computing.,Heidelberg Institute for Radiation Oncology (HIRO) and National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Christian P Karger
- Departments of Medical Physics in Radiation Oncology.,Heidelberg Institute for Radiation Oncology (HIRO) and National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Christin Glowa
- Departments of Medical Physics in Radiation Oncology.,Heidelberg Institute for Radiation Oncology (HIRO) and National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Department of Radiation Oncology and Radiotherapy, University Hospital Heidelberg, Heidelberg, Germany
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Carrara M, Massari E, Cicchetti A, Giandini T, Avuzzi B, Palorini F, Stucchi C, Fellin G, Gabriele P, Vavassori V, Degli Esposti C, Cozzarini C, Pignoli E, Fiorino C, Rancati T, Valdagni R. Development of a Ready-to-Use Graphical Tool Based on Artificial Neural Network Classification: Application for the Prediction of Late Fecal Incontinence After Prostate Cancer Radiation Therapy. Int J Radiat Oncol Biol Phys 2018; 102:1533-1542. [PMID: 30092335 DOI: 10.1016/j.ijrobp.2018.07.2014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 06/19/2018] [Accepted: 07/26/2018] [Indexed: 12/13/2022]
Abstract
PURPOSE This study was designed to apply artificial neural network (ANN) classification methods for the prediction of late fecal incontinence (LFI) after high-dose prostate cancer radiation therapy and to develop a ready-to-use graphical tool. MATERIALS AND METHODS In this study, 598 men recruited in 2 national multicenter trials were analyzed. Information was recorded on comorbidity, previous abdominal surgery, use of drugs, and dose distribution. Fecal incontinence was prospectively evaluated through self-reported questionnaires. To develop the ANN, the study population was randomly split into training (n = 300), validation (n = 149), and test (n = 149) sets. Mean grade of longitudinal LFI (ie, expressed as the average incontinence grade over the first 3 years after radiation therapy) ≥1 was considered the endpoint. A suitable subset of variables able to better predict LFI was selected by simulating 100,000 ANN configurations. The search for the definitive ANN was then performed by varying the number of inputs and hidden neurons from 4 to 5 and from 1 to 9, respectively. A final classification model was established as the average of the best 5 among 500 ANNs with the same architecture. An ANN-based graphical method to compute LFI prediction was developed to include one continuous and n dichotomous variables. RESULTS An ANN architecture was selected, with 5 input variables (mean dose, previous abdominal surgery, use of anticoagulants, use of antihypertensive drugs, and use of neoadjuvant and adjuvant hormone therapy) and 4 hidden neurons. The developed classification model correctly identified patients with LFI with 80.8% sensitivity and 63.7% ± 1.0% specificity and an area under the curve of 0.78. The developed graphical tool may efficiently classify patients in low, intermediate, and high LFI risk classes. CONCLUSIONS An ANN-based model was developed to predict LFI. The model was translated in a ready-to-use graphical tool for LFI risk classification, with direct interpretation of the role of the predictors.
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Affiliation(s)
- Mauro Carrara
- Department of Medical Physics, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy.
| | - Eleonora Massari
- Department of Medical Physics, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Alessandro Cicchetti
- Prostate Cancer Program, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Tommaso Giandini
- Department of Medical Physics, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Barbara Avuzzi
- Department of Radiation Oncology 1, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Federica Palorini
- Prostate Cancer Program, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Claudio Stucchi
- Department of Medical Physics, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Giovanni Fellin
- Department of Radiation Oncology, Ospedale Santa Chiara, Trento, Italy
| | - Pietro Gabriele
- Department of Radiation Oncology, Istituto di Candiolo-Fondazione del Piemonte per l'Oncologia IRCCS, Candiolo, Italy
| | - Vittorio Vavassori
- Department of Radiation Oncology, Cliniche Gavazzeni-Humanitas, Bergamo, Italy
| | | | - Cesare Cozzarini
- Department of Radiation Oncology, San Raffaele Scientific Institute, Milano, Italy
| | - Emanuele Pignoli
- Department of Medical Physics, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Claudio Fiorino
- Department of Medical Physics, San Raffaele Scientific Institute, Milano, Italy
| | - Tiziana Rancati
- Prostate Cancer Program, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Riccardo Valdagni
- Prostate Cancer Program, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy; Department of Radiation Oncology 1, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy; Department of Oncology and Hemato-oncology, Università degli Studi di Milano, Milan, Italy
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Incorporating Oxygen-Enhanced MRI into Multi-Parametric Assessment of Human Prostate Cancer. Diagnostics (Basel) 2017; 7:diagnostics7030048. [PMID: 28837092 PMCID: PMC5617948 DOI: 10.3390/diagnostics7030048] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 08/13/2017] [Accepted: 08/21/2017] [Indexed: 12/18/2022] Open
Abstract
Hypoxia is associated with prostate tumor aggressiveness, local recurrence, and biochemical failure. Magnetic resonance imaging (MRI) offers insight into tumor pathophysiology and recent reports have related transverse relaxation rate (R2*) and longitudinal relaxation rate (R1) measurements to tumor hypoxia. We have investigated the inclusion of oxygen-enhanced MRI for multi-parametric evaluation of tumor malignancy. Multi-parametric MRI sequences at 3 Tesla were evaluated in 10 patients to investigate hypoxia in prostate cancer prior to radical prostatectomy. Blood oxygen level dependent (BOLD), tissue oxygen level dependent (TOLD), dynamic contrast enhanced (DCE), and diffusion weighted imaging MRI were intercorrelated and compared with the Gleason score. The apparent diffusion coefficient (ADC) was significantly lower in tumor than normal prostate. Baseline R2* (BOLD-contrast) was significantly higher in tumor than normal prostate. Upon the oxygen breathing challenge, R2* decreased significantly in the tumor tissue, suggesting improved vascular oxygenation, however changes in R1 were minimal. R2* of contralateral normal prostate decreased in most cases upon oxygen challenge, although the differences were not significant. Moderate correlation was found between ADC and Gleason score. ADC and R2* were correlated and trends were found between Gleason score and R2*, as well as maximum-intensity-projection and area-under-the-curve calculated from DCE. Tumor ADC and R2* have been associated with tumor hypoxia, and thus the correlations are of particular interest. A multi-parametric approach including oxygen-enhanced MRI is feasible and promises further insights into the pathophysiological information of tumor microenvironment.
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Belfatto A, Vidal Urbinati AM, Ciardo D, Franchi D, Cattani F, Lazzari R, Jereczek-Fossa BA, Orecchia R, Baroni G, Cerveri P. Comparison between model-predicted tumor oxygenation dynamics and vascular-/flow-related Doppler indices. Med Phys 2017; 44:2011-2019. [PMID: 28273332 DOI: 10.1002/mp.12192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 01/25/2017] [Accepted: 02/24/2017] [Indexed: 11/06/2022] Open
Abstract
PURPOSE Mathematical modeling is a powerful and flexible method to investigate complex phenomena. It discloses the possibility of reproducing expensive as well as invasive experiments in a safe environment with limited costs. This makes it suitable to mimic tumor evolution and response to radiotherapy although the reliability of the results remains an issue. Complexity reduction is therefore a critical aspect in order to be able to compare model outcomes to clinical data. Among the factors affecting treatment efficacy, tumor oxygenation is known to play a key role in radiotherapy response. In this work, we aim at relating the oxygenation dynamics, predicted by a macroscale model trained on tumor volumetric data of uterine cervical cancer patients, to vascularization and blood flux indices assessed on Ultrasound Doppler images. METHODS We propose a macroscale model of tumor evolution based on three dynamics, namely active portion, necrotic portion, and oxygenation. The model parameters were assessed on the volume size of seven cervical cancer patients administered with 28 fractions of intensity modulated radiation therapy (IMRT) (1.8 Gy/fraction). For each patient, five Doppler ultrasound tests were acquired before, during, and after the treatment. The lesion was manually contoured by an expert physician using 4D View® (General Electric Company - Fairfield, Connecticut, United States), which automatically provided the overall tumor volume size along with three vascularization and/or blood flow indices. Volume data only were fed to the model for training purpose, while the predicted oxygenation was compared a posteriori to the measured Doppler indices. RESULTS The model was able to fit the tumor volume evolution within 8% error (range: 3-8%). A strong correlation between the intrapatient longitudinal indices from Doppler measurements and oxygen predicted by the model (about 90% or above) was found in three cases. Two patients showed an average correlation value (50-70%) and the remaining two presented poor correlations. The latter patients were the ones featuring the smallest tumor reduction throughout the treatment, typical of hypoxic conditions. Moreover, the average oxygenation value predicted by the model was close to the average vascularization-flow index (average difference: 7%). CONCLUSIONS The results suggest that the modeled relation between tumor evolution and oxygen dynamics was reasonable enough to provide realistic oxygenation curves in five cases (correlation greater than 50%) out of seven. In case of nonresponsive tumors, the model failed in predicting the oxygenation trend while succeeded in reproducing the average oxygenation value according to the mean vascularization-flow index. Despite the need for deeper investigations, the outcomes of the present work support the hypothesis that a simple macroscale model of tumor response to radiotherapy is able to predict the tumor oxygenation. The possibility of an objective and quantitative validation on imaging data discloses the possibility to translate them as decision support tools in clinical practice and to move a step forward in the treatment personalization.
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Affiliation(s)
- Antonella Belfatto
- Department of Electronics, Information and Bioengineering (DEIB), Politecnico di Milano University, Piazza Leonardo da Vinci, 32 - 20133, Milan, Italy
| | - Ailyn M Vidal Urbinati
- Preventive Gynecology Unit, Division of Gynecology, European Institute of Oncology, Via Giuseppe Ripamonti, 435 - 20141, Milan, Italy
| | - Delia Ciardo
- Department of Radiation Oncology, European Institute of Oncology, Via Giuseppe Ripamonti, 435 - 20141, Milan, Italy
| | - Dorella Franchi
- Preventive Gynecology Unit, Division of Gynecology, European Institute of Oncology, Via Giuseppe Ripamonti, 435 - 20141, Milan, Italy
| | - Federica Cattani
- Unit of Medical Physics, European Institute of Oncology, Via Giuseppe Ripamonti, 435 - 20141, Milan, Italy
| | - Roberta Lazzari
- Department of Radiation Oncology, European Institute of Oncology, Via Giuseppe Ripamonti, 435 - 20141, Milan, Italy
| | - Barbara A Jereczek-Fossa
- Department of Radiation Oncology, European Institute of Oncology, Via Giuseppe Ripamonti, 435 - 20141, Milan, Italy.,Department of Oncology and Hemato-oncology, University of Milan, Via Festa del Perdono, 7 - 20122, Milan, Italy
| | - Roberto Orecchia
- Department of Oncology and Hemato-oncology, University of Milan, Via Festa del Perdono, 7 - 20122, Milan, Italy.,Department of Medical Imaging and Radiation Sciences, European Institute of Oncology, Via Giuseppe Ripamonti, 435 - 20141, Milan, Italy
| | - Guido Baroni
- Department of Electronics, Information and Bioengineering (DEIB), Politecnico di Milano University, Piazza Leonardo da Vinci, 32 - 20133, Milan, Italy
| | - Pietro Cerveri
- Department of Electronics, Information and Bioengineering (DEIB), Politecnico di Milano University, Piazza Leonardo da Vinci, 32 - 20133, Milan, Italy
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