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McWilliam A, Palma G, Abravan A, Acosta O, Appelt A, Aznar M, Monti S, Onjukka E, Panettieri V, Placidi L, Rancati T, Vasquez Osorio E, Witte M, Cella L. Voxel-based analysis: Roadmap for clinical translation. Radiother Oncol 2023; 188:109868. [PMID: 37683811 DOI: 10.1016/j.radonc.2023.109868] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 07/11/2023] [Accepted: 08/20/2023] [Indexed: 09/10/2023]
Abstract
Voxel-based analysis (VBA) allows the full, 3-dimensional, dose distribution to be considered in radiotherapy outcome analysis. This provides new insights into anatomical variability of pathophysiology and radiosensitivity by removing the need for a priori definition of organs assumed to drive the dose response associated with patient outcomes. This approach may offer powerful biological insights demonstrating the heterogeneity of the radiobiology across tissues and potential associations of the radiotherapy dose with further factors. As this methodological approach becomes established, consideration needs to be given to translating VBA results to clinical implementation for patient benefit. Here, we present a comprehensive roadmap for VBA clinical translation. Technical validation needs to demonstrate robustness to methodology, where clinical validation must show generalisability to external datasets and link to a plausible pathophysiological hypothesis. Finally, clinical utility requires demonstration of potential benefit for patients in order for successful translation to be feasible. For each step on the roadmap, key considerations are discussed and recommendations provided for best practice.
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Affiliation(s)
- Alan McWilliam
- The Division of Cancer Sciences, The University of Manchester, Manchester, UK; The Christie NHS Foundation Trust, Manchester, UK.
| | - Giuseppe Palma
- Institute of Nanotechnology, National Research Council, Lecce, Italy.
| | - Azadeh Abravan
- The Division of Cancer Sciences, The University of Manchester, Manchester, UK; The Christie NHS Foundation Trust, Manchester, UK
| | - Oscar Acosta
- University Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, F-35000, Rennes, France
| | - Ane Appelt
- Leeds Institute of Medical Research at St James's, University of Leeds, Leeds, UK
| | - Marianne Aznar
- The Division of Cancer Sciences, The University of Manchester, Manchester, UK; The Christie NHS Foundation Trust, Manchester, UK
| | - Serena Monti
- Institute of Biostructures and Bioimaging, National Research Council, Naples, Italy
| | - Eva Onjukka
- Department of Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, Sweden
| | - Vanessa Panettieri
- Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Central Clinical School, Monash University, Melbourne, VIC, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Victoria 3010, Australia
| | - Lorenzo Placidi
- Fondazione Policlinico Universitario "Agostino Gemelli" IRCCS, Rome, Italy
| | - Tiziana Rancati
- Data Science Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milano, Italy
| | - Eliana Vasquez Osorio
- The Division of Cancer Sciences, The University of Manchester, Manchester, UK; The Christie NHS Foundation Trust, Manchester, UK
| | - Marnix Witte
- Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Laura Cella
- Institute of Biostructures and Bioimaging, National Research Council, Naples, Italy
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Alborghetti L, Castriconi R, Sosa Marrero C, Tudda A, Ubeira-Gabellini MG, Broggi S, Pascau J, Cubero L, Cozzarini C, De Crevoisier R, Rancati T, Acosta O, Fiorino C. Selective sparing of bladder and rectum sub-regions in radiotherapy of prostate cancer combining knowledge-based automatic planning and multicriteria optimization. Phys Imaging Radiat Oncol 2023; 28:100488. [PMID: 37694264 PMCID: PMC10482897 DOI: 10.1016/j.phro.2023.100488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 08/22/2023] [Accepted: 08/23/2023] [Indexed: 09/12/2023] Open
Abstract
Background and Purpose The association between dose to selected bladder and rectum symptom-related sub-regions (SRS) and late toxicity after prostate cancer radiotherapy has been evidenced by voxel-wise analyses. The aim of the current study was to explore the feasibility of combining knowledge-based (KB) and multi-criteria optimization (MCO) to spare SRSs without compromising planning target volume (PTV) dose delivery, including pelvic-node irradiation. Materials and Methods Forty-five previously treated patients (74.2 Gy/28fr) were selected and SRSs (in the bladder, associated with late dysuria/hematuria/retention; in the rectum, associated with bleeding) were generated using deformable registration. A KB model was used to obtain clinically suitable plans (KB-plan). KB-plans were further optimized using MCO, aiming to reduce dose to the SRSs while safeguarding target dose coverage, homogeneity and avoiding worsening dose volume histograms of the whole bladder, rectum and other organs at risk. The resulting MCO-generated plans were examined to identify the best-compromise plan (KB + MCO-plan). Results The mean SRS dose decreased in almost all patients for each SRS. D1% also decreased in the large majority, less frequently for dysuria/bleeding SRS. Mean differences were statistically significant (p < 0.05) and ranged between 1.3 and 2.2 Gy with maximum reduction of mean dose up to 3-5 Gy for the four SRSs. The better sparing of SRSs was obtained without compromising PTVs coverage. Conclusions Selectively sparing SRSs without compromising PTV coverage is feasible and has the potential to reduce toxicities in prostate cancer radiotherapy. Further investigation to better quantify the expected risk reduction of late toxicities is warranted.
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Affiliation(s)
- Lisa Alborghetti
- IRCCS San Raffaele Scientific Institute, Medical Physics, Milano, Italy
| | | | - Carlos Sosa Marrero
- CLCC Eugène Marquis, INSERM, LTSI—UMR1099, F-35000, Univ Rennes, Rennes, France
| | - Alessia Tudda
- IRCCS San Raffaele Scientific Institute, Medical Physics, Milano, Italy
| | | | - Sara Broggi
- IRCCS San Raffaele Scientific Institute, Medical Physics, Milano, Italy
| | - Javier Pascau
- Universidad Carlos III de Madrid, Bioengineering Department, Madrid, Spain
| | - Lucia Cubero
- Universidad Carlos III de Madrid, Bioengineering Department, Madrid, Spain
| | - Cesare Cozzarini
- IRCCS San Raffaele Scientific Institute, Radiotherapy, Milano, Italy
| | | | - Tiziana Rancati
- Fondazione IRCCS Istituto Nazionale dei Tumori (INT), Progetto Prostata, Milano, Italy
| | - Oscar Acosta
- CLCC Eugène Marquis, INSERM, LTSI—UMR1099, F-35000, Univ Rennes, Rennes, France
| | - Claudio Fiorino
- IRCCS San Raffaele Scientific Institute, Medical Physics, Milano, Italy
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Sosa-Marrero C, Acosta O, Pasquier D, Thariat J, Delpon G, Fiorino C, Rancatti T, Malard O, Foray N, de Crevoisier R. Voxel-wise analysis: A powerful tool to predict radio-induced toxicity and potentially perform personalised planning in radiotherapy. Cancer Radiother 2023; 27:638-642. [PMID: 37517974 DOI: 10.1016/j.canrad.2023.06.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 06/27/2023] [Indexed: 08/01/2023]
Abstract
Dose - volume histograms have been historically used to study the relationship between the planned radiation dose and healthy tissue damage. However, this approach considers neither spatial information nor heterogenous radiosensitivity within organs at risk, depending on the tissue. Recently, voxel-wise analyses have emerged in the literature as powerful tools to fully exploit three-dimensional information from the planned dose distribution. They allow to identify anatomical subregions of one or several organs in which the irradiation dose is associated with a given toxicity. These methods rely on an accurate anatomical alignment, usually obtained by means of a non-rigid registration. Once the different anatomies are spatially normalised, correlations between the three-dimensional dose and a given toxicity can be explored voxel-wise. Parametric or non-parametric statistical tests can be performed on every voxel to identify the voxels in which the dose is significantly different between patients presenting or not toxicity. Several anatomical subregions associated with genitourinary, gastrointestinal, cardiac, pulmonary or haematological toxicity have already been identified in the literature for prostate, head and neck or thorax irradiation. Voxel-wise analysis appears therefore first particularly interesting to increase toxicity prediction capability by identifying specific subregions in the organs at risk whose irradiation is highly predictive of specific toxicity. The second interest is potentially to decrease the radio-induced toxicity by limiting the dose in the predictive subregions, while not decreasing the dose in the target volume. Limitations of the approach have been pointed out.
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Affiliation(s)
- C Sosa-Marrero
- Université de Rennes, CLCC Eugène-Marquis, Inserm, LTSI - UMR 1099, 35000 Rennes, France
| | - O Acosta
- Université de Rennes, CLCC Eugène-Marquis, Inserm, LTSI - UMR 1099, 35000 Rennes, France
| | - D Pasquier
- Radiotherapy Department, centre Oscar-Lambret, 59000 Lille, France; Université de Lille, CNRS, école centrale de Lille, Cristal UMR 9189, Lille, France
| | - J Thariat
- Department of Radiation Oncology, centre François-Baclesse, 14000 Caen, France
| | - G Delpon
- Medical physics department, institut de cancérologie de l'Ouest, IMT Atlantique, Nantes université, CNRS/IN2P3, Subatech, Nantes, France
| | - C Fiorino
- Medical Physics, San Raffaele Scientific Institute, Via Olgettina 690, 20132 Milan, Italy
| | - T Rancatti
- Data Science Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - O Malard
- Service de chirurgie oto-rhinolaryngologique (ORL) et chirurgie cervicofaciale, Hôtel-Dieu, CHU de Nantes, Nantes, France
| | - N Foray
- Centre Léon-Bérard, Inserm U1296 "Radiation: Defense/Health/Environment", 69008 Lyon, France
| | - R de Crevoisier
- Université de Rennes, CLCC Eugène-Marquis, Inserm, LTSI - UMR 1099, 35000 Rennes, France; Département de radiothérapie, centre Eugène-Marquis, 35000 Rennes, France.
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Chourak H, Barateau A, Tahri S, Cadin C, Lafond C, Nunes JC, Boue-Rafle A, Perazzi M, Greer PB, Dowling J, de Crevoisier R, Acosta O. Quality assurance for MRI-only radiation therapy: A voxel-wise population-based methodology for image and dose assessment of synthetic CT generation methods. Front Oncol 2022; 12:968689. [PMID: 36300084 PMCID: PMC9589295 DOI: 10.3389/fonc.2022.968689] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
The quality assurance of synthetic CT (sCT) is crucial for safe clinical transfer to an MRI-only radiotherapy planning workflow. The aim of this work is to propose a population-based process assessing local errors in the generation of sCTs and their impact on dose distribution. For the analysis to be anatomically meaningful, a customized interpatient registration method brought the population data to the same coordinate system. Then, the voxel-based process was applied on two sCT generation methods: a bulk-density method and a generative adversarial network. The CT and MRI pairs of 39 patients treated by radiotherapy for prostate cancer were used for sCT generation, and 26 of them with delineated structures were selected for analysis. Voxel-wise errors in sCT compared to CT were assessed for image intensities and dose calculation, and a population-based statistical test was applied to identify the regions where discrepancies were significant. The cumulative histograms of the mean absolute dose error per volume of tissue were computed to give a quantitative indication of the error for each generation method. Accurate interpatient registration was achieved, with mean Dice scores higher than 0.91 for all organs. The proposed method produces three-dimensional maps that precisely show the location of the major discrepancies for both sCT generation methods, highlighting the heterogeneity of image and dose errors for sCT generation methods from MRI across the pelvic anatomy. Hence, this method provides additional information that will assist with both sCT development and quality control for MRI-based planning radiotherapy.
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Affiliation(s)
- Hilda Chourak
- University of Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
- The Australian eHealth Research Centre, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Health and Biosecurity, Brisbane, QLD, Australia
- *Correspondence: Hilda Chourak, ; Jason Dowling,
| | - Anaïs Barateau
- University of Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Safaa Tahri
- University of Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Capucine Cadin
- University of Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Caroline Lafond
- University of Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Jean-Claude Nunes
- University of Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Adrien Boue-Rafle
- University of Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Mathias Perazzi
- University of Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Peter B. Greer
- School of Mathematical and Physical Sciences, University of Newcastle, Newcastle, NSW, Australia
- Radiation Oncology, Calvary Mater Newcastle Hospital, Newcastle, NSW, Australia
| | - Jason Dowling
- The Australian eHealth Research Centre, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Health and Biosecurity, Brisbane, QLD, Australia
- *Correspondence: Hilda Chourak, ; Jason Dowling,
| | - Renaud de Crevoisier
- University of Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Oscar Acosta
- University of Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
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Omidi A, Weiss E, Wilson JS, Rosu-Bubulac M. Quantitative assessment of intra- and inter-modality deformable image registration of the heart, left ventricle, and thoracic aorta on longitudinal 4D-CT and MR images. J Appl Clin Med Phys 2021; 23:e13500. [PMID: 34962065 PMCID: PMC8833287 DOI: 10.1002/acm2.13500] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 09/17/2021] [Accepted: 11/29/2021] [Indexed: 12/25/2022] Open
Abstract
Purpose Magnetic resonance imaging (MRI)‐based investigations into radiotherapy (RT)‐induced cardiotoxicity require reliable registrations of magnetic resonance (MR) imaging to planning computed tomography (CT) for correlation to regional dose. In this study, the accuracy of intra‐ and inter‐modality deformable image registration (DIR) of longitudinal four‐dimensional CT (4D‐CT) and MR images were evaluated for heart, left ventricle (LV), and thoracic aorta (TA). Methods and materials Non‐cardiac‐gated 4D‐CT and T1 volumetric interpolated breath‐hold examination (T1‐VIBE) MRI datasets from five lung cancer patients were obtained at two breathing phases (inspiration/expiration) and two time points (before treatment and 5 weeks after initiating RT). Heart, LV, and TA were manually contoured. Each organ underwent three intramodal DIRs ((A) CT modality over time, (B) MR modality over time, and (C) MR contrast effect at the same time) and two intermodal DIRs ((D) CT/MR multimodality at same time and (E) CT/MR multimodality over time). Hausdorff distance (HD), mean distance to agreement (MDA), and Dice were evaluated and assessed for compliance with American Association of Physicists in Medicine (AAPM) Task Group (TG)‐132 recommendations. Results Mean values of HD, MDA, and Dice under all registration scenarios for each region of interest ranged between 8.7 and 16.8 mm, 1.0 and 2.6 mm, and 0.85 and 0.95, respectively, and were within the TG‐132 recommended range (MDA < 3 mm, Dice > 0.8). Intramodal DIR showed slightly better results compared to intermodal DIR. Heart and TA demonstrated higher registration accuracy compared to LV for all scenarios except for HD and Dice values in Group A. Significant differences for each metric and tissue of interest were noted between Groups B and D and between Groups B and E. MDA and Dice significantly differed between LV and heart in all registrations except for MDA in Group E. Conclusions DIR of the heart, LV, and TA between non‐cardiac‐gated longitudinal 4D‐CT and MRI across two modalities, breathing phases, and pre/post‐contrast is acceptably accurate per AAPM TG‐132 guidelines. This study paves the way for future evaluation of RT‐induced cardiotoxicity and its related factors using multimodality DIR.
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Affiliation(s)
- Alireza Omidi
- Department of Biomedical Engineering, College of Engineering, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Elisabeth Weiss
- Department of Radiation Oncology, Virginia Commonwealth University Health, Richmond, Virginia, USA
| | - John S Wilson
- Department of Biomedical Engineering, College of Engineering, Virginia Commonwealth University, Richmond, Virginia, USA.,Pauley Heart Center, Virginia Commonwealth University Health System, Richmond, Virginia, USA
| | - Mihaela Rosu-Bubulac
- Department of Radiation Oncology, Virginia Commonwealth University Health, Richmond, Virginia, USA
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Palma G, Monti S, Pacelli R, Liao Z, Deasy JO, Mohan R, Cella L. Radiation Pneumonitis in Thoracic Cancer Patients: Multi-Center Voxel-Based Analysis. Cancers (Basel) 2021; 13:cancers13143553. [PMID: 34298767 PMCID: PMC8306650 DOI: 10.3390/cancers13143553] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/07/2021] [Accepted: 07/14/2021] [Indexed: 12/12/2022] Open
Abstract
Simple Summary The pathophysiology of radiation pneumonitis (RP) after thoracic cancer radiation treatments is still not completely understood although the identification of underlying RP mechanisms may improve the therapeutic window of thoracic cancer patients. The aim of our retrospective study was to explore the dose–response patterns associated with RP by a multi-center voxel-based analysis. In a heterogeneously treated population of 382 thoracic cancer patients, we confirmed the previously described heart–lung interaction in the development of RP. The empowerment of VBA with a novel description of dose map spatial properties based on probabilistic independent component analysis (PICA) and connectograms provided valuable additional and independent information on the radiobiology of RP. Abstract This study investigates the dose–response patterns associated with radiation pneumonitis (RP) in patients treated for thoracic malignancies with different radiation modalities. To this end, voxel-based analysis (VBA) empowered by a novel strategy for the characterization of spatial properties of dose maps was applied. Data from 382 lung cancer and mediastinal lymphoma patients from three institutions treated with different radiation therapy (RT) techniques were analyzed. Each planning CT and biologically effective dose map (α/β = 3 Gy) was spatially normalized on a common anatomical reference. The VBA of local dose differences between patients with and without RP was performed and the clusters of voxels with dose differences that significantly correlated with RP at a p-level of 0.05 were generated accordingly. The robustness of VBA inference was evaluated by a novel characterization for spatial properties of dose maps based on probabilistic independent component analysis (PICA) and connectograms. This lays robust foundations to the obtained findings that the lower parts of the lungs and the heart play a prominent role in the development of RP. Connectograms showed that the dataset can support a radiobiological differentiation between the main heart and lung substructures.
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Affiliation(s)
- Giuseppe Palma
- Institute of Biostructures and Bioimaging, National Research Council, 80145 Napoli, Italy;
- Correspondence: (G.P.); (L.C.)
| | - Serena Monti
- Institute of Biostructures and Bioimaging, National Research Council, 80145 Napoli, Italy;
| | - Roberto Pacelli
- Department of Advanced Biomedical Sciences, University of Naples “Federico II”, 80131 Napoli, Italy;
| | - Zhongxing Liao
- Department of Radiation Oncology, MD Anderson Cancer Center, Houston, TX 77030, USA;
| | - Joseph O. Deasy
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA;
| | - Radhe Mohan
- Department of Radiation Physics, MD Anderson Cancer Center, Houston, TX 77030, USA;
| | - Laura Cella
- Institute of Biostructures and Bioimaging, National Research Council, 80145 Napoli, Italy;
- Correspondence: (G.P.); (L.C.)
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Zhou B, Augenfeld Z, Chapiro J, Zhou SK, Liu C, Duncan JS. Anatomy-guided multimodal registration by learning segmentation without ground truth: Application to intraprocedural CBCT/MR liver segmentation and registration. Med Image Anal 2021; 71:102041. [PMID: 33823397 PMCID: PMC8184611 DOI: 10.1016/j.media.2021.102041] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 03/04/2021] [Accepted: 03/10/2021] [Indexed: 12/24/2022]
Abstract
Multimodal image registration has many applications in diagnostic medical imaging and image-guided interventions, such as Transcatheter Arterial Chemoembolization (TACE) of liver cancer guided by intraprocedural CBCT and pre-operative MR. The ability to register peri-procedurally acquired diagnostic images into the intraprocedural environment can potentially improve the intra-procedural tumor targeting, which will significantly improve therapeutic outcomes. However, the intra-procedural CBCT often suffers from suboptimal image quality due to lack of signal calibration for Hounsfield unit, limited FOV, and motion/metal artifacts. These non-ideal conditions make standard intensity-based multimodal registration methods infeasible to generate correct transformation across modalities. While registration based on anatomic structures, such as segmentation or landmarks, provides an efficient alternative, such anatomic structure information is not always available. One can train a deep learning-based anatomy extractor, but it requires large-scale manual annotations on specific modalities, which are often extremely time-consuming to obtain and require expert radiological readers. To tackle these issues, we leverage annotated datasets already existing in a source modality and propose an anatomy-preserving domain adaptation to segmentation network (APA2Seg-Net) for learning segmentation without target modality ground truth. The segmenters are then integrated into our anatomy-guided multimodal registration based on the robust point matching machine. Our experimental results on in-house TACE patient data demonstrated that our APA2Seg-Net can generate robust CBCT and MR liver segmentation, and the anatomy-guided registration framework with these segmenters can provide high-quality multimodal registrations.
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Affiliation(s)
- Bo Zhou
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA.
| | - Zachary Augenfeld
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Julius Chapiro
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT, USA
| | - S Kevin Zhou
- School of Biomedical Engineering & Suzhou Institute for Advanced Research, University of Science and Technology of China, Suzhou, China; Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China
| | - Chi Liu
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA; Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT, USA
| | - James S Duncan
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA; Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT, USA; Department of Electrical Engineering, Yale University, New Haven, CT, USA.
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Ebert MA, Gulliford S, Acosta O, de Crevoisier R, McNutt T, Heemsbergen WD, Witte M, Palma G, Rancati T, Fiorino C. Spatial descriptions of radiotherapy dose: normal tissue complication models and statistical associations. Phys Med Biol 2021; 66:12TR01. [PMID: 34049304 DOI: 10.1088/1361-6560/ac0681] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 05/28/2021] [Indexed: 12/20/2022]
Abstract
For decades, dose-volume information for segmented anatomy has provided the essential data for correlating radiotherapy dosimetry with treatment-induced complications. Dose-volume information has formed the basis for modelling those associations via normal tissue complication probability (NTCP) models and for driving treatment planning. Limitations to this approach have been identified. Many studies have emerged demonstrating that the incorporation of information describing the spatial nature of the dose distribution, and potentially its correlation with anatomy, can provide more robust associations with toxicity and seed more general NTCP models. Such approaches are culminating in the application of computationally intensive processes such as machine learning and the application of neural networks. The opportunities these approaches have for individualising treatment, predicting toxicity and expanding the solution space for radiation therapy are substantial and have clearly widespread and disruptive potential. Impediments to reaching that potential include issues associated with data collection, model generalisation and validation. This review examines the role of spatial models of complication and summarises relevant published studies. Sources of data for these studies, appropriate statistical methodology frameworks for processing spatial dose information and extracting relevant features are described. Spatial complication modelling is consolidated as a pathway to guiding future developments towards effective, complication-free radiotherapy treatment.
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Affiliation(s)
- Martin A Ebert
- School of Physics, Mathematics and Computing, University of Western Australia, Crawley, Western Australia, Australia
- Department of Radiation Oncology, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia
- 5D Clinics, Claremont, Western Australia, Australia
| | - Sarah Gulliford
- Department of Radiotherapy Physics, University College Hospitals London, United Kingdom
- Department of Medical Physics and Bioengineering, University College London, United Kingdom
| | - Oscar Acosta
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI-UMR 1099, F-35000 Rennes, France
| | | | - Todd McNutt
- Johns Hopkins University, Baltimore, Maryland, United States of America
| | | | - Marnix Witte
- The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Giuseppe Palma
- Institute of Biostructures and Bioimaging, National Research Council, Napoli, Italy
| | - Tiziana Rancati
- Prostate Cancer Program, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Claudio Fiorino
- Medical Physics, San Raffaele Scientific Institute, Milano, Italy
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Lafond C, Barateau A, N'Guessan J, Perichon N, Delaby N, Simon A, Haigron P, Mylona E, Acosta O, de Crevoisier R. Planning With Patient-Specific Rectal Sub-Region Constraints Decreases Probability of Toxicity in Prostate Cancer Radiotherapy. Front Oncol 2020; 10:1597. [PMID: 33042802 PMCID: PMC7517942 DOI: 10.3389/fonc.2020.01597] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 07/23/2020] [Indexed: 11/27/2022] Open
Abstract
Background: A rectal sub-region (SRR) has been previously identified by voxel-wise analysis in the inferior-anterior part of the rectum as highly predictive of rectal bleeding (RB) in prostate cancer radiotherapy. Translating the SRR to patient-specific radiotherapy planning is challenging as new constraints have to be defined. A recent geometry-based model proposed to optimize the planning by determining the achievable mean doses (AMDs) to the organs at risk (OARs), taking into account the overlap between the planning target volume (PTV) and OAR. The aim of this study was to quantify the SRR dose sparing by using the AMD model in the planning, while preserving the dose to the prostate. Material and Methods: Three-dimensional volumetric modulated arc therapy (VMAT) planning dose distributions for 60 patients were computed following four different strategies, delivering 78 Gy to the prostate, while meeting the genitourinary group dose constraints to the OAR: (i) a standard plan corresponding to the standard practice for rectum sparing (STDpl), (ii) a plan adding constraints to SRR (SRRpl), (iii) a plan using the AMD model applied to the rectum only (AMD_RECTpl), and (iv) a final plan using the AMD model applied to both the rectum and the SRR (AMD_RECT_SRRpl). After PTV dose normalization, plans were compared with regard to dose distributions, quality, and estimated risk of RB using a normal tissue complication probability model. Results: AMD_RECT_SRRpl showed the largest SRR dose sparing, with significant mean dose reductions of 7.7, 3, and 2.3 Gy, with respect to the STDpl, SRRpl, and AMD_RECTpl, respectively. AMD_RECT_SRRpl also decreased the mean rectal dose by 3.6 Gy relative to STDpl and by 3.3 Gy relative to SRRpl. The absolute risk of grade ≥1 RB decreased from 22.8% using STDpl planning to 17.6% using AMD_RECT_SRRpl considering SRR volume. AMD_RECT_SRRpl plans, however, showed slightly less dose homogeneity and significant increase of the number of monitor units, compared to the three other strategies. Conclusion: Compared to a standard prostate planning, applying dose constraints to a patient-specific SRR by using the achievable mean dose model decreased the mean dose by 7.7 Gy to the SRR and may decrease the relative risk of RB by 22%.
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Affiliation(s)
- Caroline Lafond
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Anaïs Barateau
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Joël N'Guessan
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Nicolas Perichon
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Nolwenn Delaby
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Antoine Simon
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Pascal Haigron
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Eugenia Mylona
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
| | - Oscar Acosta
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, Rennes, France
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10
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Shelley LEA, Sutcliffe MPF, Thomas SJ, Noble DJ, Romanchikova M, Harrison K, Bates AM, Burnet NG, Jena R. Associations between voxel-level accumulated dose and rectal toxicity in prostate radiotherapy. PHYSICS & IMAGING IN RADIATION ONCOLOGY 2020; 14:87-94. [PMID: 32582869 PMCID: PMC7301619 DOI: 10.1016/j.phro.2020.05.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 05/15/2020] [Accepted: 05/18/2020] [Indexed: 12/25/2022]
Abstract
Background and Purpose Associations between dose and rectal toxicity in prostate radiotherapy are generally poorly understood. Evaluating spatial dose distributions to the rectal wall (RW) may lead to improvements in dose-toxicity modelling by incorporating geometric information, masked by dose-volume histograms. Furthermore, predictive power may be strengthened by incorporating the effects of interfraction motion into delivered dose calculations.Here we interrogate 3D dose distributions for patients with and without toxicity to identify rectal subregions at risk (SRR), and compare the discriminatory ability of planned and delivered dose. Material and Methods Daily delivered dose to the rectum was calculated using image guidance scans, and accumulated at the voxel level using biomechanical finite element modelling. SRRs were statistically determined for rectal bleeding, proctitis, faecal incontinence and stool frequency from a training set (n = 139), and tested on a validation set (n = 47). Results SRR patterns differed per endpoint. Analysing dose to SRRs improved discriminative ability with respect to the full RW for three of four endpoints. Training set AUC and OR analysis produced stronger toxicity associations from accumulated dose than planned dose. For rectal bleeding in particular, accumulated dose to the SRR (AUC 0.76) improved upon dose-toxicity associations derived from planned dose to the RW (AUC 0.63). However, validation results could not be considered significant. Conclusions Voxel-level analysis of dose to the RW revealed SRRs associated with rectal toxicity, suggesting non-homogeneous intra-organ radiosensitivity. Incorporating spatial features of accumulated delivered dose improved dose-toxicity associations. This may be an important tool for adaptive radiotherapy in the future.
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Affiliation(s)
- Leila E A Shelley
- Cancer Research UK VoxTox Research Group, Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom.,Edinburgh Cancer Centre, Western General Hospital, Edinburgh EH4 2XU, United Kingdom.,Department of Engineering, University of Cambridge, Trumpington St, Cambridge CB21PZ, United Kingdom
| | - Michael P F Sutcliffe
- Cancer Research UK VoxTox Research Group, Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom.,Department of Engineering, University of Cambridge, Trumpington St, Cambridge CB21PZ, United Kingdom
| | - Simon J Thomas
- Cancer Research UK VoxTox Research Group, Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom.,Department of Medical Physics and Clinical Engineering, Cambridge University Hospitals NHS Foundation Trust, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom
| | - David J Noble
- Cancer Research UK VoxTox Research Group, Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom.,Department of Oncology, University of Cambridge, Cambridge Biomedical Campus, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, United Kingdom
| | - Marina Romanchikova
- Cancer Research UK VoxTox Research Group, Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom.,National Physical Laboratory, Teddington TW11 0JE, United Kingdom
| | - Karl Harrison
- Cancer Research UK VoxTox Research Group, Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom.,Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Amy M Bates
- Cancer Research UK VoxTox Research Group, Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom.,Cambridge Clinical Trials Unit, Cambridge University Hospitals NHS Foundation Trust, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom
| | - Neil G Burnet
- Cancer Research UK VoxTox Research Group, Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom.,University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PL, United Kingdom
| | - Raj Jena
- Cancer Research UK VoxTox Research Group, Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom.,Department of Oncology, University of Cambridge, Cambridge Biomedical Campus, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, United Kingdom
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11
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Palma G, Monti S, Cella L. Voxel-based analysis in radiation oncology: A methodological cookbook. Phys Med 2020; 69:192-204. [PMID: 31923757 DOI: 10.1016/j.ejmp.2019.12.013] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 12/16/2019] [Accepted: 12/17/2019] [Indexed: 12/20/2022] Open
Abstract
Recently, 2D or 3D methods for dose distribution analysis have been proposed as evolutions of the Dose Volume Histogram (DVH) approaches. Those methods, collectively referred to as pixel- or voxel-based (VB) methods, evaluate local dose response patterns and go beyond the organ-based philosophy of Normal Tissue Complication Probability (NTCP) modelling. VB methods have been introduced in the context of radiation oncology in the very last years following the virtuous example of neuroimaging experience. In radiation oncology setting, dose mapping is a suitable scheme to compare spatial patterns of local dose distributions between patients who develop toxicity and who do not. In this critical review, we present the methods that include spatial dose distribution information for evaluating different toxicity endpoints after radiation therapy. The review addresses two main topics. First, the critical aspects in dose map building, namely the spatial normalization of the dose distributions from different patients. Then, the issues related to the actual dose map comparison, i.e. the viable options for a robust VB statistical analysis and the potential pitfalls related to the adopted solutions. To elucidate the different theoretical and technical issues, the covered topics are illustrated in relation to practical applications found in the existing literature. We conclude the overview on the VB philosophy in radiation oncology by introducing new phenomenological approaches to NTCP modelling that accounts for inhomogeneous organ radiosensitivity.
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Affiliation(s)
- G Palma
- National Research Council, Institute of Biostructures and Bioimaging, Napoli, Italy.
| | - S Monti
- National Research Council, Institute of Biostructures and Bioimaging, Napoli, Italy
| | - L Cella
- National Research Council, Institute of Biostructures and Bioimaging, Napoli, Italy
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12
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Nakamura M, Nakao M, Hirashima H, Iramina H, Mizowaki T. Performance evaluation of a newly developed three-dimensional model-based global-to-local registration in prostate cancer. JOURNAL OF RADIATION RESEARCH 2019; 60:595-602. [PMID: 31135904 PMCID: PMC6805968 DOI: 10.1093/jrr/rrz031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 03/26/2019] [Indexed: 06/09/2023]
Abstract
We evaluated the performance of a newly developed three-dimensional (3D) model-based global-to-local registration of multiple organs, by comparing it with a 3D model-based global registration in the prostate region. This study included 220 prostate cancer patients who underwent intensity-modulated radiotherapy or volumetric-modulated arc therapy. Our registration proceeded sequentially, i.e. global registration including affine and piece-wise affine transformation followed by local registration. As a local registration, Laplacian-based and finite element method-based registration was implemented in Algorithm A and B, respectively. Algorithm C was for global registration alone. The template models for the prostate, seminal vesicles, rectum and bladder were constructed from the first 20 patients, and then three different registrations were performed on these organs for the remaining 200 patients, to assess registration accuracy. The 75th percentile Hausdorff distance was <1 mm in Algorithm A; it was >1 mm in Algorithm B, except for the prostate; and 3.9 mm for the prostate and >7.8 mm for other organs in Algorithm C. The median computation time to complete registration was <101, 30 and 16 s in Algorithms A, B and C, respectively. Analysis of variance revealed significant differences among Algorithms A-C in the Hausdorff distance and computation time. In addition, no significant difference was observed in the difference of Hausdorff distance between Algorithm A and B with Tukey's multiple comparison test. The 3D model-based global-to-local registration, especially that implementing Laplacian-based registration, completed surface registration rapidly and provided sufficient registration accuracy in the prostate region.
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Affiliation(s)
- Mitsuhiro Nakamura
- Division of Medical Physics, Department of Information Technology and Medical Engineering, Human Health Sciences, Graduate School of Medicine, Kyoto University, Japan
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Japan
| | - Megumi Nakao
- Department of Systems Science, Graduate School of Informatics, Kyoto University, Japan
| | - Hideaki Hirashima
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Japan
| | - Hiraku Iramina
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Japan
| | - Takashi Mizowaki
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Japan
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13
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Palma G, Monti S, Conson M, Pacelli R, Cella L. Normal tissue complication probability (NTCP) models for modern radiation therapy. Semin Oncol 2019; 46:210-218. [PMID: 31506196 DOI: 10.1053/j.seminoncol.2019.07.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 07/31/2019] [Indexed: 02/07/2023]
Abstract
Mathematical models of normal tissue complication probability (NTCP) able to robustly predict radiation-induced morbidities (RIM) play an essential role in the identification of a personalized optimal plan, and represent the key to maximizing the benefits of technological advances in radiation therapy (RT). Most modern RT techniques pose, however, new challenges in estimating the risk of RIM. The aim of this report is to schematically review NTCP models in the framework of advanced radiation therapy techniques. Issues relevant to hypofractionated stereotactic body RT and ion beam therapy are critically reviewed. Reirradiation scenarios for new or recurrent malignances and NTCP are also illustrated. A new phenomenological approach to predict RIM is suggested.
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Affiliation(s)
- Giuseppe Palma
- National Research Council, Institute of Biostructures and Bioimaging, Napoli, Italy
| | - Serena Monti
- National Research Council, Institute of Biostructures and Bioimaging, Napoli, Italy
| | - Manuel Conson
- Department of Advanced Biomedical Sciences, Federico II University School of Medicine, Naples, Italy
| | - Roberto Pacelli
- Department of Advanced Biomedical Sciences, Federico II University School of Medicine, Naples, Italy
| | - Laura Cella
- National Research Council, Institute of Biostructures and Bioimaging, Napoli, Italy.
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14
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Palma G, Monti S, Thor M, Rimner A, Deasy JO, Cella L. Spatial signature of dose patterns associated with acute radiation-induced lung damage in lung cancer patients treated with stereotactic body radiation therapy. Phys Med Biol 2019; 64:155006. [PMID: 31261141 DOI: 10.1088/1361-6560/ab2e16] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Thoracic radiation therapy (RT) is often associated with lung side effects, whose etiology is still controversial. Our aim was to explore correlations between local dose in the thoracic anatomy and the radiation-induced lung damage (RILD). To this end, we designed a robust scheme for voxel-based analysis (VBA) to explore dose patterns associated with RILD in non-small-cell lung cancer (NSCLC) patients receiving stereotactic body RT (SBRT). We analyzed 106 NSCLC SBRT patients (median prescription dose: 50 Gy; range: [40-54] Gy) in 4 fractions (range: [3-5]) with clinical and dosimetric records suitable for the analysis. The incidence of acute G1 RILD (RTOG grade ⩾ 1) was 68%. Each planning CT and dose map was spatially normalized to a common anatomical reference using a B-spline inter-patient registration algorithm after masking the gross tumor volume. The tumor-subtracted dose maps were converted into biologically effective dose maps (α/β = 3 Gy). VBA was performed according to a non-parametric permutation test accounting for multiple comparison, based on a cluster analysis method. The underlying general linear model of RILD was designed to include dose maps and each non-dosimetric variable significantly correlated with RILD. The clusters of voxels with dose differences significantly correlated with RILD at a given p -level (S p ) were generated. The only non-dosimetric variable significantly correlated with RILD was the chronic obstructive pulmonary disease (p = 0.034). Patients with G1 RILD received significantly (p ⩽ 0.05) higher doses in two voxel clusters S 0.05 in the lower-left lung (14 cm3) and in an area (64 cm3) largely included within the ventricles. The applied VBA represents a powerful tool to probe the dose susceptibility of inhomogeneous organs in clinical radiobiology studies. The identified subregions with dose differences associated with G1 RILD in both the heart and lower lungs endorse a trend of previously reported hypotheses on lung toxicity radiobiology.
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Affiliation(s)
- Giuseppe Palma
- Institute of Biostructures and Bioimaging, National Research Council (CNR), Via T. De Amicis, 95, 80145, Napoli, Italy. Author to whom any correspondence should be addressed
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15
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Rigaud B, Simon A, Castelli J, Lafond C, Acosta O, Haigron P, Cazoulat G, de Crevoisier R. Deformable image registration for radiation therapy: principle, methods, applications and evaluation. Acta Oncol 2019; 58:1225-1237. [PMID: 31155990 DOI: 10.1080/0284186x.2019.1620331] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Background: Deformable image registration (DIR) is increasingly used in the field of radiation therapy (RT) to account for anatomical deformations. The aims of this paper are to describe the main applications of DIR in RT and discuss current DIR evaluation methods. Methods: Articles on DIR published from January 2000 to October 2018 were extracted from PubMed and Science Direct. Our search was restricted to articles that report data obtained from humans, were written in English, and address DIR methods for RT. A total of 207 articles were selected from among 2506 identified in the search process. Results: At planning, DIR is used for organ delineation using atlas-based segmentation, deformation-based planning target volume definition, functional planning and magnetic resonance imaging-based dose calculation. In image-guided RT, DIR is used for contour propagation and dose calculation on per-treatment imaging. DIR is also used to determine the accumulated dose from fraction to fraction in external beam RT and brachytherapy, both for dose reporting and adaptive RT. In the case of re-irradiation, DIR can be used to estimate the cumulated dose of the two irradiations. Finally, DIR can be used to predict toxicity in voxel-wise population analysis. However, the evaluation of DIR remains an open issue, especially when dealing with complex cases such as the disappearance of matter. To quantify DIR uncertainties, most evaluation methods are limited to geometry-based metrics. Software companies have now integrated DIR tools into treatment planning systems for clinical use, such as contour propagation and fraction dose accumulation. Conclusions: DIR is increasingly important in RT applications, from planning to toxicity prediction. DIR is routinely used to reduce the workload of contour propagation. However, its use for complex dosimetric applications must be carefully evaluated by combining quantitative and qualitative analyses.
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Affiliation(s)
- Bastien Rigaud
- CLCC Eugène Marquis, University of Rennes, Inserm , Rennes , France
| | - Antoine Simon
- CLCC Eugène Marquis, University of Rennes, Inserm , Rennes , France
| | - Joël Castelli
- CLCC Eugène Marquis, University of Rennes, Inserm , Rennes , France
| | - Caroline Lafond
- CLCC Eugène Marquis, University of Rennes, Inserm , Rennes , France
| | - Oscar Acosta
- CLCC Eugène Marquis, University of Rennes, Inserm , Rennes , France
| | - Pascal Haigron
- CLCC Eugène Marquis, University of Rennes, Inserm , Rennes , France
| | - Guillaume Cazoulat
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center , Houston , TX , USA
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16
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Sjöholm T, Ekström S, Strand R, Ahlström H, Lind L, Malmberg F, Kullberg J. A whole-body FDG PET/MR atlas for multiparametric voxel-based analysis. Sci Rep 2019; 9:6158. [PMID: 30992502 PMCID: PMC6467986 DOI: 10.1038/s41598-019-42613-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 04/04/2019] [Indexed: 01/12/2023] Open
Abstract
Quantitative multiparametric imaging is a potential key application for Positron Emission Tomography/Magnetic Resonance (PET/MR) hybrid imaging. To enable objective and automatic voxel-based multiparametric analysis in whole-body applications, the purpose of this study was to develop a multimodality whole-body atlas of functional 18F-fluorodeoxyglucose (FDG) PET and anatomical fat-water MR data of adults. Image registration was used to transform PET/MR images of healthy control subjects into male and female reference spaces, producing a fat-water MR, local tissue volume and FDG PET whole-body normal atlas consisting of 12 male (66.6 ± 6.3 years) and 15 female (69.5 ± 3.6 years) subjects. Manual segmentations of tissues and organs in the male and female reference spaces confirmed that the atlas contained adequate physiological and anatomical values. The atlas was applied in two anomaly detection tasks as proof of concept. The first task automatically detected anomalies in two subjects with suspected malignant disease using FDG data. The second task successfully detected abnormal liver fat infiltration in one subject using fat fraction data.
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Affiliation(s)
- Therese Sjöholm
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
| | - Simon Ekström
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
| | - Robin Strand
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
- Department of Information Technology, Uppsala University, Uppsala, Sweden
| | - Håkan Ahlström
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
- Antaros Medical AB, Mölndal, Sweden
| | - Lars Lind
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Filip Malmberg
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
- Department of Information Technology, Uppsala University, Uppsala, Sweden
| | - Joel Kullberg
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
- Antaros Medical AB, Mölndal, Sweden
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17
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Palma G, Monti S, Xu T, Scifoni E, Yang P, Hahn SM, Durante M, Mohan R, Liao Z, Cella L. Spatial Dose Patterns Associated With Radiation Pneumonitis in a Randomized Trial Comparing Intensity-Modulated Photon Therapy With Passive Scattering Proton Therapy for Locally Advanced Non-Small Cell Lung Cancer. Int J Radiat Oncol Biol Phys 2019; 104:1124-1132. [PMID: 30822531 DOI: 10.1016/j.ijrobp.2019.02.039] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 01/31/2019] [Accepted: 02/20/2019] [Indexed: 12/27/2022]
Abstract
PURPOSE Radiation pneumonitis (RP) is commonly associated with thoracic radiation therapy, and its incidence is related to dose and volume of the normal lung in the path of radiation. Our aim was to investigate dose patterns associated with RP in patients enrolled in a randomized trial of intensity modulated radiation therapy (IMRT) versus passive scattering proton therapy (PSPT) for locally advanced non-small cell lung cancer. METHODS We analyzed 178 patients prospectively treated with PSPT or IMRT for non-small cell lung cancer to a prescribed dose of 66 or 74 Gy in conventional daily fractionation with concurrent chemotherapy. Forty patients (22%) developed clinically symptomatic RP. Voxel-based analysis of local dose differences was done with a nonparametric permutation test accounting for multiple comparisons. From the obtained 3-dimensional significance maps, we derived clusters of voxels that exhibited dose differences between groups at a statistical significance level of 0.05. RESULTS The voxel-based analysis highlighted that (1) significant dose differences between patients with and without RP were found in the lower part of the lungs and in the heart and (2) the anatomic regions significantly spared by PSPT and the clusters in which doses were significantly correlated with RP development were disjoint. CONCLUSIONS The analyzed trial data provide an unprecedented opportunity to substantiate previous hypotheses regarding the role of the heart and the lower lungs in the development of RP. Knowledge of this relationship between RP and thoracic regional radiosensitivity should be considered in clinical practice and in the design of future trials.
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Affiliation(s)
- Giuseppe Palma
- National Research Council, Institute of Biostructures and Bioimaging, Napoli, Italy
| | - Serena Monti
- IRCCS SDN, Image Processing Department, Napoli, Italy
| | - Ting Xu
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Emanuele Scifoni
- Istituto Nazionale di Fisica Nucleare, Trento Institute for Fundamental Physics and Applications, Trento, Italy
| | - Pei Yang
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Stephen M Hahn
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Marco Durante
- Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany; Technische Universität Darmstadt, Institut für Festkörperphysik, Darmstadt, Germany
| | - Radhe Mohan
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Zhongxing Liao
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
| | - Laura Cella
- National Research Council, Institute of Biostructures and Bioimaging, Napoli, Italy
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18
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Mylona E, Acosta O, Lizee T, Lafond C, Crehange G, Magné N, Chiavassa S, Supiot S, Ospina Arango JD, Campillo-Gimenez B, Castelli J, de Crevoisier R. Voxel-Based Analysis for Identification of Urethrovesical Subregions Predicting Urinary Toxicity After Prostate Cancer Radiation Therapy. Int J Radiat Oncol Biol Phys 2019; 104:343-354. [PMID: 30716523 DOI: 10.1016/j.ijrobp.2019.01.088] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Revised: 01/22/2019] [Accepted: 01/26/2019] [Indexed: 12/18/2022]
Abstract
PURPOSE To apply a voxel-based analysis to identify urethrovesical symptom-related subregions (SRSs) associated with acute and late urinary toxicity in prostate cancer radiation therapy. METHODS AND MATERIALS Two hundred seventy-two patients with prostate cancer treated with intensity-modulated radiation therapy/image-guided radiation therapy were analyzed prospectively. Each patient's computed tomography imaging was spatially normalized to a common coordinate system via nonrigid registration. The obtained deformation fields were used to map the dose of each patient to the common coordinate system. A voxel-based statistical analysis was applied to generate 3-dimensional dose-volume maps for different urinary symptoms, allowing the identification of corresponding SRSs with statistically significant dose differences between patients with or without toxicity. Each SRS was propagated back to each individual's native space, and dose-volume histograms (DVHs) for the SRSs and the whole bladder were computed. Logistic and Cox regression were used to estimate the SRS's prediction capability compared with the whole bladder. RESULTS A local dose-effect relationship was found in the bladder and the urethra. SRSs were identified for 5 symptoms: acute incontinence in the urethra, acute retention in the bladder trigone, late retention and dysuria in the posterior part of the bladder, and late hematuria in the superior part of the bladder, with significant dose differences between patients with and without toxicity, ranging from 1.2 to 9.3 Gy. The doses to the SRSs were significantly predictive of toxicity, with maximum areas under the receiver operating characteristic curve of 0.73 for acute incontinence, 0.62 for acute retention, 0.70 for late retention, 0.81 for late dysuria, and 0.67 for late hematuria. The bladder DVH was predictive only for late retention, dysuria, and hematuria (area under the curve, 0.65-0.72). CONCLUSIONS The dose delivered to the urethra and the posterior and superior parts of the bladder was predictive of acute incontinence and retention and of late retention, dysuria, and hematuria. The dose to the whole bladder was moderately predictive.
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Affiliation(s)
- Eugenia Mylona
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, F-35000 Rennes, France
| | - Oscar Acosta
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, F-35000 Rennes, France
| | - Thibaut Lizee
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, F-35000 Rennes, France
| | - Caroline Lafond
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, F-35000 Rennes, France
| | - Gilles Crehange
- Department of Radiation Oncology, Centre Georges François Leclerc, Dijon, France
| | - Nicolas Magné
- Department of Radiation Oncology, Lucien Neuwirth Cancer Institute, St Priest en Jarez, France
| | - Sophie Chiavassa
- Department of Radiation Oncology, Institut de Cancérologie de l'Ouest, Saint Herblain, France
| | - Stéphane Supiot
- Department of Radiation Oncology, Institut de Cancérologie de l'Ouest, Saint Herblain, France
| | - Juan David Ospina Arango
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, F-35000 Rennes, France; Universidad Nacional de Colombia, Medellin, Colombia
| | | | - Joel Castelli
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, F-35000 Rennes, France
| | - Renaud de Crevoisier
- Univ Rennes, CLCC Eugène Marquis, INSERM, LTSI - UMR 1099, F-35000 Rennes, France.
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Independent component analysis for rectal bleeding prediction following prostate cancer radiotherapy. Radiother Oncol 2017; 126:263-269. [PMID: 29203291 DOI: 10.1016/j.radonc.2017.11.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 11/18/2017] [Accepted: 11/20/2017] [Indexed: 11/22/2022]
Abstract
BACKGROUND AND PURPOSE To evaluate the benefit of independent component analysis (ICA)-based models for predicting rectal bleeding (RB) following prostate cancer radiotherapy. MATERIALS AND METHODS A total of 593 irradiated prostate cancer patients were prospectively analyzed for Grade ≥2 RB. ICA was used to extract two informative subspaces (presenting RB or not) from the rectal DVHs, enabling a set of new pICA parameters to be estimated. These DVH-based parameters, along with others from the principal component analysis (PCA) and functional PCA, were compared to "standard" features (patient/treatment characteristics and DVH bins) using the Cox proportional hazards model for RB prediction. The whole cohort was divided into: (i) training (N = 339) for ICA-based subspace identification and Cox regression model identification and (ii) validation (N = 254) for RB prediction capability evaluation using the C-index and the area under the receiving operating curve (AUC), by comparing predicted and observed toxicity probabilities. RESULTS In the training cohort, multivariate Cox analysis retained pICA and PC as significant parameters of RB with 0.65 C-index. For the validation cohort, the C-index increased from 0.64 when pICA was not included in the Cox model to 0.78 when including pICA parameters. When pICA was not included, the AUC for 3-, 5-, and 8-year RB prediction were 0.68, 0.66, and 0.64, respectively. When included, the AUC increased to 0.83, 0.80, and 0.78, respectively. CONCLUSION Among the many various extracted or calculated features, ICA parameters improved RB prediction following prostate cancer radiotherapy.
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Acosta O, Mylona E, Le Dain M, Voisin C, Lizee T, Rigaud B, Lafond C, Gnep K, de Crevoisier R. Multi-atlas-based segmentation of prostatic urethra from planning CT imaging to quantify dose distribution in prostate cancer radiotherapy. Radiother Oncol 2017; 125:492-499. [PMID: 29031609 DOI: 10.1016/j.radonc.2017.09.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 08/27/2017] [Accepted: 09/15/2017] [Indexed: 01/01/2023]
Abstract
BACKGROUND AND PURPOSE Segmentation of intra-prostatic urethra for dose assessment from planning CT may help explaining urinary toxicity in prostate cancer radiotherapy. This work sought to: i) propose an automatic method for urethra segmentation in CT, ii) compare it with previously proposed surrogate models and iii) quantify the dose received by the urethra in patients treated with IMRT. MATERIALS AND METHODS A weighted multi-atlas-based urethra segmentation method was devised from a training data set of 55 CT scans of patients receiving brachytherapy with visible urinary catheters. Leave-one-out cross validation was performed to quantify the error between the urethra segmentation and the catheter ground truth with two scores: the centerlines distance (CLD) and the percentage of centerline within a certain distance from the catheter (PWR). The segmentation method was then applied to a second test data set of 95 prostate cancer patients having received 78Gy IMRT to quantify dose to the urethra. RESULTS Mean CLD was 3.25±1.2mm for the whole urethra and 3.7±1.7mm, 2.52±1.5mm, and 3.01±1.7mm for the top, middle, and bottom thirds, respectively. In average, 53% of the segmented centerlines were within a radius<3.5mm from the centerline ground truth and 83% in a radius<5mm. The proposed method outperformed existing surrogate models. In IMRT, urethra DVH was significantly higher than prostate DVH from V74Gy to V79Gy. CONCLUSION A multi-atlas-based segmentation method was proposed enabling assessment of the dose within the prostatic urethra.
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Affiliation(s)
- Oscar Acosta
- INSERM U1099, Rennes, France; Université de Rennes 1 - Laboratoire du Traitement du Signal et de l'Image, France.
| | - Eugenia Mylona
- INSERM U1099, Rennes, France; Université de Rennes 1 - Laboratoire du Traitement du Signal et de l'Image, France
| | - Mathieu Le Dain
- INSERM U1099, Rennes, France; Université de Rennes 1 - Laboratoire du Traitement du Signal et de l'Image, France
| | - Camille Voisin
- INSERM U1099, Rennes, France; Université de Rennes 1 - Laboratoire du Traitement du Signal et de l'Image, France
| | - Thibaut Lizee
- INSERM U1099, Rennes, France; Université de Rennes 1 - Laboratoire du Traitement du Signal et de l'Image, France
| | - Bastien Rigaud
- INSERM U1099, Rennes, France; Université de Rennes 1 - Laboratoire du Traitement du Signal et de l'Image, France
| | - Carolina Lafond
- INSERM U1099, Rennes, France; Université de Rennes 1 - Laboratoire du Traitement du Signal et de l'Image, France; Centre Eugene Marquis, Département de Radiothérapie, Rennes, France
| | - Khemara Gnep
- INSERM U1099, Rennes, France; Université de Rennes 1 - Laboratoire du Traitement du Signal et de l'Image, France; Centre Eugene Marquis, Département de Radiothérapie, Rennes, France
| | - Renaud de Crevoisier
- INSERM U1099, Rennes, France; Université de Rennes 1 - Laboratoire du Traitement du Signal et de l'Image, France; Centre Eugene Marquis, Département de Radiothérapie, Rennes, France
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Shelley LEA, Scaife JE, Romanchikova M, Harrison K, Forman JR, Bates AM, Noble DJ, Jena R, Parker MA, Sutcliffe MPF, Thomas SJ, Burnet NG. Delivered dose can be a better predictor of rectal toxicity than planned dose in prostate radiotherapy. Radiother Oncol 2017; 123:466-471. [PMID: 28460825 PMCID: PMC5486775 DOI: 10.1016/j.radonc.2017.04.008] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 04/03/2017] [Accepted: 04/05/2017] [Indexed: 01/23/2023]
Abstract
Background and purpose For the first time, delivered dose to the rectum has been calculated and accumulated throughout the course of prostate radiotherapy using megavoltage computed tomography (MVCT) image guidance scans. Dosimetric parameters were linked with toxicity to test the hypothesis that delivered dose is a stronger predictor of toxicity than planned dose. Material and methods Dose–surface maps (DSMs) of the rectal wall were automatically generated from daily MVCT scans for 109 patients within the VoxTox research programme. Accumulated-DSMs, representing total delivered dose, and planned-DSMs, from planning CT data, were parametrised using Equivalent Uniform Dose (EUD) and ‘DSM dose-width’, the lateral dimension of an ellipse fitted to a discrete isodose cluster. Associations with 6 toxicity endpoints were assessed using receiver operator characteristic curve analysis. Results For rectal bleeding, the area under the curve (AUC) was greater for accumulated dose than planned dose for DSM dose-widths up to 70 Gy. Accumulated 65 Gy DSM dose-width produced the strongest spatial correlation (AUC 0.664), while accumulated EUD generated the largest AUC overall (0.682). For proctitis, accumulated EUD was the only reportable predictor (AUC 0.673). Accumulated EUD was systematically lower than planned EUD. Conclusions Dosimetric parameters extracted from accumulated DSMs have demonstrated stronger correlations with rectal bleeding and proctitis, than planned DSMs.
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Affiliation(s)
- L E A Shelley
- Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, United Kingdom; Department of Medical Physics and Clinical Engineering, Cambridge University Hospitals NHS Foundation Trust, United Kingdom; Department of Engineering, University of Cambridge, United Kingdom.
| | - J E Scaife
- Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, United Kingdom; Department of Oncology, University of Cambridge, United Kingdom
| | - M Romanchikova
- Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, United Kingdom; Department of Medical Physics and Clinical Engineering, Cambridge University Hospitals NHS Foundation Trust, United Kingdom
| | - K Harrison
- Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, United Kingdom; Cavendish Laboratory, University of Cambridge, United Kingdom
| | - J R Forman
- Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, United Kingdom; Cambridge Clinical Trials Unit, Cambridge University Hospitals NHS Foundation Trust, United Kingdom
| | - A M Bates
- Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, United Kingdom; Department of Oncology, University of Cambridge, United Kingdom
| | - D J Noble
- Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, United Kingdom; Department of Oncology, University of Cambridge, United Kingdom
| | - R Jena
- Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, United Kingdom; Department of Oncology, University of Cambridge, United Kingdom
| | - M A Parker
- Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, United Kingdom; Cavendish Laboratory, University of Cambridge, United Kingdom
| | - M P F Sutcliffe
- Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, United Kingdom; Department of Engineering, University of Cambridge, United Kingdom
| | - S J Thomas
- Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, United Kingdom; Department of Medical Physics and Clinical Engineering, Cambridge University Hospitals NHS Foundation Trust, United Kingdom
| | - N G Burnet
- Cambridge University Hospitals NHS Foundation Trust, Department of Oncology, United Kingdom; Department of Oncology, University of Cambridge, United Kingdom
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Moulton CR, House MJ, Lye V, Tang CI, Krawiec M, Joseph DJ, Denham JW, Ebert MA. Spatial features of dose-surface maps from deformably-registered plans correlate with late gastrointestinal complications. Phys Med Biol 2017; 62:4118-4139. [PMID: 28445167 DOI: 10.1088/1361-6560/aa663d] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
This study investigates the associations between spatial distribution of dose to the rectal surface and observed gastrointestinal toxicities after deformably registering each phase of a combined external beam radiotherapy (EBRT)/high-dose-rate brachytherapy (HDRBT) prostate cancer treatment. The study contains data for 118 patients where the HDRBT CT was deformably-registered to the EBRT CT. The EBRT and registered HDRBT TG43 dose distributions in a reference 2 Gy/fraction were 3D-summed. Rectum dose-surface maps (DSMs) were obtained by virtually unfolding the rectum surface slice-by-slice. Associations with late peak gastrointestinal toxicities were investigated using voxel-wise DSM analysis as well as parameterised spatial patterns. The latter were obtained by thresholding DSMs from 1-80 Gy (increment = 1) and extracting inferior-superior extent, left-right extent, area, perimeter, compactness, circularity and ellipse fit parameters. Logistic regressions and Mann-Whitney U-tests were used to correlate features with toxicities. Rectal bleeding, stool frequency, diarrhoea and urgency/tenesmus were associated with greater lateral and/or longitudinal spread of the high doses near the anterior rectal surface. Rectal bleeding and stool frequency were also influenced by greater low-intermediate doses to the most inferior 20% of the rectum and greater low-intermediate-high doses to 40-80% of the rectum length respectively. Greater low-intermediate doses to the superior 20% and inferior 20% of the rectum length were associated with anorectal pain and urgency/tenesmus respectively. Diarrhoea, completeness of evacuation and proctitis were also related to greater low doses to the posterior side of the rectum. Spatial features for the intermediate-high dose regions such as area, perimeter, compactness, circularity, ellipse eccentricity and confinement to ellipse fits were strongly associated with toxicities other than anorectal pain. Consequently, toxicity is related to the shape of isodoses as well as dose coverage. The findings indicate spatial constraints on doses to certain sections of the rectum may be important for reducing toxicities and optimising dose.
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Affiliation(s)
- Calyn R Moulton
- School of Physics, University of Western Australia, Crawley, Western Australia, Australia
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23
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Dréan G, Acosta O, Lafond C, Simon A, de Crevoisier R, Haigron P. Interindividual registration and dose mapping for voxelwise population analysis of rectal toxicity in prostate cancer radiotherapy. Med Phys 2016; 43:2721-2730. [DOI: 10.1118/1.4948501] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
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