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Pandey S, Kutuk T, Abdalah MA, Stringfield O, Ravi H, Mills MN, Graham JA, Latifi K, Moreno WA, Ahmed KA, Raghunand N. Prediction of radiologic outcome-optimized dose plans and post-treatment magnetic resonance images: A proof-of-concept study in breast cancer brain metastases treated with stereotactic radiosurgery. Phys Imaging Radiat Oncol 2024; 31:100602. [PMID: 39040435 PMCID: PMC11261135 DOI: 10.1016/j.phro.2024.100602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 06/14/2024] [Accepted: 06/20/2024] [Indexed: 07/24/2024] Open
Abstract
Background and purpose Information in multiparametric Magnetic Resonance (mpMR) images is relatable to voxel-level tumor response to Radiation Treatment (RT). We have investigated a deep learning framework to predict (i) post-treatment mpMR images from pre-treatment mpMR images and the dose map ("forward models"), and, (ii) the RT dose map that will produce prescribed changes within the Gross Tumor Volume (GTV) on post-treatment mpMR images ("inverse model"), in Breast Cancer Metastases to the Brain (BCMB) treated with Stereotactic Radiosurgery (SRS). Materials and methods Local outcomes, planning computed tomography (CT) images, dose maps, and pre-treatment and post-treatment Apparent Diffusion Coefficient of water (ADC) maps, T1-weighted unenhanced (T1w) and contrast-enhanced (T1wCE), T2-weighted (T2w) and Fluid-Attenuated Inversion Recovery (FLAIR) mpMR images were curated from 39 BCMB patients. mpMR images were co-registered to the planning CT and intensity-calibrated. A 2D pix2pix architecture was used to train 5 forward models (ADC, T2w, FLAIR, T1w, T1wCE) and 1 inverse model on 1940 slices from 18 BCMB patients, and tested on 437 slices from another 9 BCMB patients. Results Root Mean Square Percent Error (RMSPE) within the GTV between predicted and ground-truth post-RT images for the 5 forward models, in 136 test slices containing GTV, were (mean ± SD) 0.12 ± 0.044 (ADC), 0.14 ± 0.066 (T2w), 0.08 ± 0.038 (T1w), 0.13 ± 0.058 (T1wCE), and 0.09 ± 0.056 (FLAIR). RMSPE within the GTV on the same 136 test slices, between the predicted and ground-truth dose maps, was 0.37 ± 0.20 for the inverse model. Conclusions A deep learning-based approach for radiologic outcome-optimized dose planning in SRS of BCMB has been demonstrated.
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Affiliation(s)
- Shraddha Pandey
- Department of Cancer Physiology, Moffitt Cancer Center, Tampa, FL 33612, USA
- Department of Electrical Engineering, University of South Florida, Tampa, FL 33612, USA
| | - Tugce Kutuk
- Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA
| | - Mahmoud A. Abdalah
- Quantitative Imaging Shared Service, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA
| | - Olya Stringfield
- Quantitative Imaging Shared Service, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA
| | - Harshan Ravi
- Department of Cancer Physiology, Moffitt Cancer Center, Tampa, FL 33612, USA
| | - Matthew N. Mills
- Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA
| | - Jasmine A. Graham
- Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA
- Department of Oncologic Sciences, University of South Florida, Tampa, FL 33612, USA
| | - Kujtim Latifi
- Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA
- Department of Oncologic Sciences, University of South Florida, Tampa, FL 33612, USA
| | - Wilfrido A. Moreno
- Department of Electrical Engineering, University of South Florida, Tampa, FL 33612, USA
| | - Kamran A. Ahmed
- Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA
- Department of Oncologic Sciences, University of South Florida, Tampa, FL 33612, USA
| | - Natarajan Raghunand
- Department of Cancer Physiology, Moffitt Cancer Center, Tampa, FL 33612, USA
- Department of Oncologic Sciences, University of South Florida, Tampa, FL 33612, USA
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Thorwarth D. Clinical use of positron emission tomography for radiotherapy planning - Medical physics considerations. Z Med Phys 2023; 33:13-21. [PMID: 36272949 PMCID: PMC10068574 DOI: 10.1016/j.zemedi.2022.09.001] [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: 04/13/2022] [Revised: 08/17/2022] [Accepted: 09/21/2022] [Indexed: 11/06/2022]
Abstract
PET/CT imaging plays an increasing role in radiotherapy treatment planning. The aim of this article was to identify the major use cases and technical as well as medical physics challenges during integration of these data into treatment planning. Dedicated aspects, such as (i) PET/CT-based radiotherapy simulation, (ii) PET-based target volume delineation, (iii) functional avoidance to optimized organ-at-risk sparing and (iv) functionally adapted individualized radiotherapy are discussed in this article. Furthermore, medical physics aspects to be taken into account are summarized and presented in form of check-lists.
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Affiliation(s)
- Daniela Thorwarth
- Section for Biomedical Physics, Department of Radiation Oncology, University of Tübingen, Tübingen, Germany; German Cancer Consortium (DKTK), partner site Tübingen; and German Cancer Research Center (DKFZ), Heidelberg, Germany.
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Brighi C, Keall PJ, Holloway LC, Walker A, Whelan B, de Witt Hamer PC, Verburg N, Aly F, Chen C, Koh ES, Waddington DEJ. An investigation of the conformity, feasibility, and expected clinical benefits of multiparametric MRI-guided dose painting radiotherapy in glioblastoma. Neurooncol Adv 2022; 4:vdac134. [PMID: 36105390 PMCID: PMC9466270 DOI: 10.1093/noajnl/vdac134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Background New technologies developed to improve survival outcomes for glioblastoma (GBM) continue to have limited success. Recently, image-guided dose painting (DP) radiotherapy has emerged as a promising strategy to increase local control rates. In this study, we evaluate the practical application of a multiparametric MRI model of glioma infiltration for DP radiotherapy in GBM by measuring its conformity, feasibility, and expected clinical benefits against standard of care treatment. Methods Maps of tumor probability were generated from perfusion/diffusion MRI data from 17 GBM patients via a previously developed model of GBM infiltration. Prescriptions for DP were linearly derived from tumor probability maps and used to develop dose optimized treatment plans. Conformity of DP plans to dose prescriptions was measured via a quality factor. Feasibility of DP plans was evaluated by dose metrics to target volumes and critical brain structures. Expected clinical benefit of DP plans was assessed by tumor control probability. The DP plans were compared to standard radiotherapy plans. Results The conformity of the DP plans was >90%. Compared to the standard plans, DP (1) did not affect dose delivered to organs at risk; (2) increased mean and maximum dose and improved minimum dose coverage for the target volumes; (3) reduced minimum dose within the radiotherapy treatment margins; (4) improved local tumor control probability within the target volumes for all patients. Conclusions A multiparametric MRI model of GBM infiltration can enable conformal, feasible, and potentially beneficial dose painting radiotherapy plans.
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Affiliation(s)
- Caterina Brighi
- ACRF Image X Institute, Sydney School of Health Sciences, Faculty of Medicine and Health, The University of Sydney , Sydney , Australia
- Ingham Institute for Applied Medical Research , Sydney , Australia
| | - Paul J Keall
- ACRF Image X Institute, Sydney School of Health Sciences, Faculty of Medicine and Health, The University of Sydney , Sydney , Australia
- Ingham Institute for Applied Medical Research , Sydney , Australia
| | - Lois C Holloway
- Ingham Institute for Applied Medical Research , Sydney , Australia
- Department of Radiation Oncology, Liverpool and Macarthur Cancer Therapy Centres , Liverpool , Australia
- Centre for Medical Radiation Physics, University of Wollongong , Wollongong, Australia
| | - Amy Walker
- Ingham Institute for Applied Medical Research , Sydney , Australia
- Department of Radiation Oncology, Liverpool and Macarthur Cancer Therapy Centres , Liverpool , Australia
- Centre for Medical Radiation Physics, University of Wollongong , Wollongong, Australia
| | - Brendan Whelan
- ACRF Image X Institute, Sydney School of Health Sciences, Faculty of Medicine and Health, The University of Sydney , Sydney , Australia
- Ingham Institute for Applied Medical Research , Sydney , Australia
| | - Philip C de Witt Hamer
- Brain Tumor Center Amsterdam , Amsterdam UMC, Amsterdam , The Netherlands
- Department of Neurosurgery , Amsterdam UMC, Amsterdam , The Netherlands
| | - Niels Verburg
- Brain Tumor Center Amsterdam , Amsterdam UMC, Amsterdam , The Netherlands
- Department of Neurosurgery , Amsterdam UMC, Amsterdam , The Netherlands
| | - Farhannah Aly
- Ingham Institute for Applied Medical Research , Sydney , Australia
- Department of Radiation Oncology, Liverpool and Macarthur Cancer Therapy Centres , Liverpool , Australia
| | - Cathy Chen
- Department of Radiation Oncology, Liverpool and Macarthur Cancer Therapy Centres , Liverpool , Australia
| | - Eng-Siew Koh
- Ingham Institute for Applied Medical Research , Sydney , Australia
- Department of Radiation Oncology, Liverpool and Macarthur Cancer Therapy Centres , Liverpool , Australia
| | - David E J Waddington
- ACRF Image X Institute, Sydney School of Health Sciences, Faculty of Medicine and Health, The University of Sydney , Sydney , Australia
- Ingham Institute for Applied Medical Research , Sydney , Australia
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Martinez J, Subramanian K, Margolis D, O'Dwyer E, Osborne J, Jhanwar Y, Nagar H, Williams N, RoyChoudhury A, Madera G, Babich J, Huicochea Castellanos S. 68Ga-PSMA-HBED-CC PET/MRI is superior to multiparametric magnetic resonance imaging in men with biochemical recurrent prostate cancer: A prospective single-institutional study. Transl Oncol 2021; 15:101242. [PMID: 34649151 PMCID: PMC8517922 DOI: 10.1016/j.tranon.2021.101242] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/20/2021] [Accepted: 10/04/2021] [Indexed: 02/07/2023] Open
Abstract
PSMA PET/MRI has a higher true positive rate and sensitivity than mpMRI in patients with biochemically recurrent prostate cancer. The true positive rate for PSMA PET/MRI was significantly greater in patients who were post prostatectomy for primary treatment. 40% of patients with a PSA value less than 0.2 ng/mL had a positive PSMA PET/MRI read compared to 9% on MRI.
Background The primary objective was to compare the overall diagnostic performance, presented as detection rate of 68Ga-PSMA-HBED-CC positron emission tomography/magnetic resonance imaging (PSMA PET/MRI) versus conventional, multiparametric MRI (mpMRI) in a population of patients with biochemically recurrent prostate cancer. In conjunction with this analysis, secondary objectives included the evaluation of the detection rate stratified by PSA levels and primary treatment modality. Methods A total of 165 PSMA PET MRI were performed from April 2018 to May 2021, of whom 108 were presenting for biochemical recurrent disease. The PSMA PET vertex to thigh were read by two different board-certified nuclear medicine physicians while the MRI head and neck, chest, abdomen, and pelvis (with dedicated, PI-RADS compliant multiparametric prostate MRI) were read by two board certified diagnostic radiologists. Analysis PSMA PET/MRI had a higher detection rate than mpMRI when evaluating patients with biochemical recurrence (BCR) with similar results demonstrated when sub-analysis was performed using PSA levels, primary treatment modality, and time since androgen deprivation therapy. Our study also showed PSMA PET/MRI had a higher sensitivity than mpMRI. Discussion Our findings demonstrate that PSMA PET/MRI is a better imaging modality in the detection of disease in the setting of BCR when compared to MRI alone. Combined utility with PSMA PET/MRI is a powerful tool which can aid in not only the detection of disease, but also guide in treatment planning for prostate cancer patients.
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Affiliation(s)
- Juana Martinez
- Division of Molecular Imaging and Therapeutics, Department of Radiology, Weill Cornell Medicine, 525 E 68th Street, New York, NY 10065, USA
| | - Kritika Subramanian
- Division of Molecular Imaging and Therapeutics, Department of Radiology, Weill Cornell Medicine, 525 E 68th Street, New York, NY 10065, USA.
| | - Daniel Margolis
- Division of Body Imaging, Department of Radiology, Weill Cornell Medicine, New York, NY, USA
| | - Elisabeth O'Dwyer
- Division of Molecular Imaging and Therapeutics, Department of Radiology, Weill Cornell Medicine, 525 E 68th Street, New York, NY 10065, USA; Division of Body Imaging, Department of Radiology, Weill Cornell Medicine, New York, NY, USA
| | - Joseph Osborne
- Division of Molecular Imaging and Therapeutics, Department of Radiology, Weill Cornell Medicine, 525 E 68th Street, New York, NY 10065, USA
| | - Yuliya Jhanwar
- Department of Radiology, CareMount Medical, Mount Kisco, NY, USA
| | - Himanshu Nagar
- Department of Radiation Oncology, Weill Cornell Medicine, New York, NY, USA
| | - Nicholas Williams
- Division of Biostatistics, Department of Population Health Sciences, Weill Cornell Medicine, New York, NY, USA
| | - Arindam RoyChoudhury
- Division of Biostatistics, Department of Population Health Sciences, Weill Cornell Medicine, New York, NY, USA
| | - Gabriela Madera
- Department of Radiology, Weill Cornell Medicine, New York, NY, USA
| | - John Babich
- Division of Radiopharmaceutical Sciences, Department of Radiology, Weill Cornell Medicine, New York, NY, USA
| | - Sandra Huicochea Castellanos
- Division of Molecular Imaging and Therapeutics, Department of Radiology, Weill Cornell Medicine, 525 E 68th Street, New York, NY 10065, USA
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Outaggarts Z, Wegener D, Berger B, Zips D, Paulsen F, Bleif M, Thorwarth D, Alber M, Dohm O, Müller AC. Target miss using PTV-based IMRT compared to robust optimization via coverage probability concept in prostate cancer. Acta Oncol 2020; 59:911-917. [PMID: 32436467 DOI: 10.1080/0284186x.2020.1760349] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Purpose: Cure- and toxicity rates of prostate IGRT can both be affected by ill-chosen planning target volume (PTV) margins. For dose-escalated prostate radiotherapy, we studied the potential for organ at risk (OAR) sparing and compensation of prostate motion with robust plan optimization using the coverage probability (CovP) concept compared to conventional PTV-based IMRT.Material and methods: We evaluated plan quality of CovP-plans for 27 intermediate risk prostate cancer patients treated in a prospective study (78 Gy/39 fractions). Clinical target volume (CTV) and OARs were contoured on three separate CTs to capture movement and deformation. To define the internal target volume (ITV), the union of CTV1-3 was encompassed by an isotropic margin of 7 mm for the planning process. CovP-dose distribution is optimized considering weight factors for IMRT constraints derived from probabilities of systematic organ displacement in the three CTs. CovP-dose volume histograms (DVHs) were compared with additionally calculated conventional PTV-based IMRT plans. PTV-based IMRT was planned on one-single CT with an isotropically expanded CTV to generate the PTV (i.e., CTV1 + 7mm) and was evaluated on the two other CTs.Results: The CovP-concept showed higher robustness in target volume coverage. Target miss was frequently observed with PTV-based IMRT, resulting in cold spots until 70 Gy with the CovP-concept. The target dose at 74 Gy was comparable, while further the dose-escalation (75-78 Gy) was improved with PTV-based IMRT. However, dose-escalation with PTV-based IMRT was associated with increased OAR-doses, especially in high-dose areas.Conclusions: Probabilistic dose-escalated IMRT was feasible in this prospective study. Comparison of the CovP-concept with PTV-based IMRT revealed superiority with regard to target-coverage and sparing of OARs. The CovP-concept implements a robust plan optimization strategy for organ deformation and motions and could, therefore, serve as a less demanding compromise on the way to adaptive IGRT avoiding daily time-consuming re-planning. SUMMARYWe evaluated the robustness of coverage probability (CovP)-based IMRT plans within a prospective study for prostate cancer radiotherapy. The treatment plans were compared with newly calculated conventional PTV-based IMRT plans. We were able to show that CovP led to a clearly more robust target coverage by avoiding hot spots at OARs compared to conventional PTV-based IMRT. In addition, negative consequences of an inflated PTV can be ameliorated by a more relaxed CovP-based dose prescription.
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Affiliation(s)
- Zoulikha Outaggarts
- Department of Radiation Oncology, University Hospital Tübingen, Tübingen, Germany
| | - Daniel Wegener
- Department of Radiation Oncology, University Hospital Tübingen, Tübingen, Germany
| | - Bernhard Berger
- Clinic for Radiation Oncology, Oberschwaben Hospital Group, Ravensburg, Germany
| | - Daniel Zips
- Department of Radiation Oncology, University Hospital Tübingen, Tübingen, Germany
| | - Frank Paulsen
- Department of Radiation Oncology, University Hospital Tübingen, Tübingen, Germany
| | - Martin Bleif
- Clinic for Radiology and Radiation Oncology, ALB FILS Clinics Hospital on the Eichert, Goppingen, Germany
| | - Daniela Thorwarth
- Department of Radiation Oncology, Section Medical Physics, University Hospital Tübingen, Tübingen, Germany
| | - Markus Alber
- Clinic for Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany
| | - Oliver Dohm
- Department of Radiation Oncology, Section Medical Physics, University Hospital Tübingen, Tübingen, Germany
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Her EJ, Haworth A, Reynolds HM, Sun Y, Kennedy A, Panettieri V, Bangert M, Williams S, Ebert MA. Voxel-level biological optimisation of prostate IMRT using patient-specific tumour location and clonogen density derived from mpMRI. Radiat Oncol 2020; 15:172. [PMID: 32660504 PMCID: PMC7805066 DOI: 10.1186/s13014-020-01568-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 05/13/2020] [Indexed: 12/24/2022] Open
Abstract
AIMS This study aimed to develop a framework for optimising prostate intensity-modulated radiotherapy (IMRT) based on patient-specific tumour biology, derived from multiparametric MRI (mpMRI). The framework included a probabilistic treatment planning technique in the effort to yield dose distributions with an improved expected treatment outcome compared with uniform-dose planning approaches. METHODS IMRT plans were generated for five prostate cancer patients using two inverse planning methods: uniform-dose to the planning target volume and probabilistic biological optimisation for clinical target volume tumour control probability (TCP) maximisation. Patient-specific tumour location and clonogen density information were derived from mpMRI and geometric uncertainties were incorporated in the TCP calculation. Potential reduction in dose to sensitive structures was assessed by comparing dose metrics of uniform-dose plans with biologically-optimised plans of an equivalent level of expected tumour control. RESULTS The planning study demonstrated biological optimisation has the potential to reduce expected normal tissue toxicity without sacrificing local control by shaping the dose distribution to the spatial distribution of tumour characteristics. On average, biologically-optimised plans achieved 38.6% (p-value: < 0.01) and 51.2% (p-value: < 0.01) reduction in expected rectum and bladder equivalent uniform dose, respectively, when compared with uniform-dose planning. CONCLUSIONS It was concluded that varying the dose distribution within the prostate to take account for each patient's clonogen distribution was feasible. Lower doses to normal structures compared to uniform-dose plans was possible whilst providing robust plans against geometric uncertainties. Further validation in a larger cohort is warranted along with considerations for adaptive therapy and limiting urethral dose.
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Affiliation(s)
- E J Her
- School of Physics, Mathematics and Computing, University of Western Australia, Perth, Australia.
| | - A Haworth
- Institute of Medical Physics, University of Sydney, Sydney, Australia
| | - H M Reynolds
- The Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, Australia.,Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, Australia
| | - Y Sun
- The Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, Australia.,Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, Australia
| | - A Kennedy
- Department of Radiation Oncology, Sir Charles Gairdner Hospital, Perth, Australia
| | - V Panettieri
- Alfred Health Radiation Oncology, Melbourne, Australia
| | - M Bangert
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Department of Medical Physics in Radiation Oncology, Heidelberg Institute for Radiation Oncology, Heidelberg, Germany
| | - S Williams
- The Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, Australia.,Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, Melbourne, Australia
| | - M A Ebert
- School of Physics, Mathematics and Computing, University of Western Australia, Perth, Australia.,Department of Radiation Oncology, Sir Charles Gairdner Hospital, Perth, Australia.,5D Clinics, Perth, Australia
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Kurz C, Buizza G, Landry G, Kamp F, Rabe M, Paganelli C, Baroni G, Reiner M, Keall PJ, van den Berg CAT, Riboldi M. Medical physics challenges in clinical MR-guided radiotherapy. Radiat Oncol 2020; 15:93. [PMID: 32370788 PMCID: PMC7201982 DOI: 10.1186/s13014-020-01524-4] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 03/24/2020] [Indexed: 12/18/2022] Open
Abstract
The integration of magnetic resonance imaging (MRI) for guidance in external beam radiotherapy has faced significant research and development efforts in recent years. The current availability of linear accelerators with an embedded MRI unit, providing volumetric imaging at excellent soft tissue contrast, is expected to provide novel possibilities in the implementation of image-guided adaptive radiotherapy (IGART) protocols. This study reviews open medical physics issues in MR-guided radiotherapy (MRgRT) implementation, with a focus on current approaches and on the potential for innovation in IGART.Daily imaging in MRgRT provides the ability to visualize the static anatomy, to capture internal tumor motion and to extract quantitative image features for treatment verification and monitoring. Those capabilities enable the use of treatment adaptation, with potential benefits in terms of personalized medicine. The use of online MRI requires dedicated efforts to perform accurate dose measurements and calculations, due to the presence of magnetic fields. Likewise, MRgRT requires dedicated quality assurance (QA) protocols for safe clinical implementation.Reaction to anatomical changes in MRgRT, as visualized on daily images, demands for treatment adaptation concepts, with stringent requirements in terms of fast and accurate validation before the treatment fraction can be delivered. This entails specific challenges in terms of treatment workflow optimization, QA, and verification of the expected delivered dose while the patient is in treatment position. Those challenges require specialized medical physics developments towards the aim of fully exploiting MRI capabilities. Conversely, the use of MRgRT allows for higher confidence in tumor targeting and organs-at-risk (OAR) sparing.The systematic use of MRgRT brings the possibility of leveraging IGART methods for the optimization of tumor targeting and quantitative treatment verification. Although several challenges exist, the intrinsic benefits of MRgRT will provide a deeper understanding of dose delivery effects on an individual basis, with the potential for further treatment personalization.
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Affiliation(s)
- Christopher Kurz
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377, Munich, Germany
- Department of Medical Physics, Ludwig-Maximilians-Universität München, Am Coulombwall 1, 85748, Garching, Germany
| | - Giulia Buizza
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, P.za Leonardo da Vinci 32, 20133, Milano, Italy
| | - Guillaume Landry
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377, Munich, Germany
- Department of Medical Physics, Ludwig-Maximilians-Universität München, Am Coulombwall 1, 85748, Garching, Germany
- German Cancer Consortium (DKTK), 81377, Munich, Germany
| | - Florian Kamp
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377, Munich, Germany
| | - Moritz Rabe
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377, Munich, Germany
| | - Chiara Paganelli
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, P.za Leonardo da Vinci 32, 20133, Milano, Italy
| | - Guido Baroni
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, P.za Leonardo da Vinci 32, 20133, Milano, Italy
- Bioengineering Unit, National Center of Oncological Hadrontherapy (CNAO), Strada Privata Campeggi 53, 27100, Pavia, Italy
| | - Michael Reiner
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377, Munich, Germany
| | - Paul J Keall
- ACRF Image X Institute, University of Sydney, Sydney, NSW, 2006, Australia
| | - Cornelis A T van den Berg
- Department of Radiotherapy, University Medical Centre Utrecht, PO box 85500, 3508 GA, Utrecht, The Netherlands
| | - Marco Riboldi
- Department of Medical Physics, Ludwig-Maximilians-Universität München, Am Coulombwall 1, 85748, Garching, Germany.
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Witoszynskyj S, Andrzejewski P, Georg D, Hacker M, Nyholm T, Rausch I, Knäusl B. Attenuation correction of a flat table top for radiation therapy in hybrid PET/MR using CT- and 68Ge/ 68Ga transmission scan-based μ-maps. Phys Med 2019; 65:76-83. [PMID: 31437602 DOI: 10.1016/j.ejmp.2019.08.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 08/01/2019] [Accepted: 08/02/2019] [Indexed: 12/28/2022] Open
Abstract
Hybrid PET/MR offers new opportunities in radiation oncology for tissue/tumour characterisation and response assessment. Attenuation correction (AC) is an important issue especially in the presence of immobilization devices and flat table tops (FTT). The goal of this study was to compare two methods of AC using CT- and 68Ge/68Ga transmission scan-based attenuation maps (μ-maps) for a custom-designed FTT. Measurements were performed in the mMR PET/MR and TrueV PET/CT Biograph Siemens scanners with three different phantoms, namely the Siemens MR-QA, a cubic canister and the NEMA IEC body phantom. The study revealed that the MR image quality is not hampered by the presence of the FTT. For cubic canister applying the scanner's inherent AC alone resulted in inaccuracies in PET images, with up to -4.0% underestimation of the activity. The mean NEMA sphere activity measurements without FTT, agreed within 3.5% with the respective inserted activity. Placing the FTT in the PET/MR scanner resulted in a difference to the injected activity of 4.5% when the table was not corrected for. By introducing the μ-maps the discrepancy between the used activity and the measurements decreased down to 2.6%. To improve the AC of the FTT the creation of a dedicated μ-map was necessary while the CT-based μ-map performed equally good as the source transmission scan-based one.
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Affiliation(s)
- Stephan Witoszynskyj
- Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Währingergürtel 18-20, 1090 Vienna, Austria
| | - Piotr Andrzejewski
- Department of Radiotherapy, Comprehensive Cancer Center, Medical University of Vienna, Währingergürtel 18-20, 1090 Vienna, Austria; Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, Währingergürtel 18-20, 1090 Vienna, Austria
| | - Dietmar Georg
- Department of Radiotherapy, Comprehensive Cancer Center, Medical University of Vienna, Währingergürtel 18-20, 1090 Vienna, Austria; Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, Währingergürtel 18-20, 1090 Vienna, Austria
| | - Marcus Hacker
- Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Währingergürtel 18-20, 1090 Vienna, Austria
| | - Tufve Nyholm
- Department of Radiation Sciences, Umeå University, SE-90187 Umeå, Sweden
| | - Ivo Rausch
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währingergürtel 18-20, 1090 Vienna, Austria
| | - Barbara Knäusl
- Department of Radiotherapy, Comprehensive Cancer Center, Medical University of Vienna, Währingergürtel 18-20, 1090 Vienna, Austria; Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, Währingergürtel 18-20, 1090 Vienna, Austria.
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Schwenck J, Olthof SC, Pfannenberg C, Reischl G, Wegener D, Marzec J, Bedke J, Stenzl A, Nikolaou K, la Fougère C, Zips D, Müller AC. Intention-to-Treat Analysis of 68Ga-PSMA and 11C-Choline PET/CT Versus CT for Prostate Cancer Recurrence After Surgery. J Nucl Med 2019; 60:1359-1365. [DOI: 10.2967/jnumed.118.224543] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Accepted: 02/11/2019] [Indexed: 12/11/2022] Open
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11
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Sadick M, Richers J, Tuschy B, Schad LR, Schoenberg SO, Zöllner FG. Feasibility of quantitative MR-perfusion imaging to monitor treatment response after uterine artery embolization (UAE) in symptomatic uterus fibroids. Magn Reson Imaging 2019; 59:31-38. [PMID: 30807812 DOI: 10.1016/j.mri.2019.02.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 02/14/2019] [Accepted: 02/15/2019] [Indexed: 01/06/2023]
Abstract
INTRODUCTION In 25% of women, symptomatic uterus myomas are diagnosed with clinical and functional impairment ranging from abdominal and pelvic pain to dys- and hypermenorrhea, dyspareunia, pollakiuria and infertility. Women undergoing a treatment increasingly prefer nowadays minimal invasive, uterus preserving therapies like uterine artery embolization (UAE) over surgical hysterectomy, nowadays. To emphasize the efficacy of UAE as a uterus preserving treatment with targeted therapy of myomas only, analysis of tissue perfusion pre and post embolization is required. The purpose of this study was to assess treatment response in UAE in females with symptomatic uterus myomas by quantitative magnetic resonance perfusion imaging. METHODS Seven females scheduled for uterus myoma embolization underwent three MRI examinations (pre, post, follow-up) including morphological and dynamic contrast enhanced perfusion imaging at 3 T. To measure tumor volume, regions-of-interest covering the tumor and the uterus were drawn by two readers in consensus. Blood flow, blood volume, and mean transit time were calculated by a pixel-by-pixel deconvolution approach. Kruskal-Wallis/Friedman test was employed to test whether the group medians differ significantly with correction for multiple comparisons using Bonferroni method. RESULTS Change of volume could be observed in all patients after embolization but was significantly different only between pre/post and follow-up time point. Measured differences in all perfusion parameters were significant between pre-intervention and post-intervention/follow-up in the myomas, no significant differences could be detected for the uterus tissue. CONCLUSIONS Our results demonstrate devascularization of symptomatic myomas which correlates with cessation of hypermenorrhea in all treated patients without affecting healthy uterus tissue. Supplementing UAE with perfusion imaging to monitor early treatment response is feasible and might provide valuable information for the follow-up of patients and contribute to providing confidence for the patients in treatment success.
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Affiliation(s)
- Maliha Sadick
- Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer Ufer 1-3, 68167 Mannheim, Germany
| | - Jakob Richers
- Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer Ufer 1-3, 68167 Mannheim, Germany
| | - Benjamin Tuschy
- Department of Gynaecology and Obstetrics, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer Ufer 1-3, 68167 Mannheim, Germany
| | - Lothar R Schad
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer Ufer 1-3, 68167 Mannheim, Germany
| | - Stefan O Schoenberg
- Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer Ufer 1-3, 68167 Mannheim, Germany
| | - Frank G Zöllner
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer Ufer 1-3, 68167 Mannheim, Germany.
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12
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Supiot S, Rousseau C, Dore M, Chèze-Le-Rest C, Kandel-Aznar C, Potiron V, Guerif S, Paris F, Ferrer L, Campion L, Meingan P, Delpon G, Hatt M, Visvikis D. Reoxygenation during radiotherapy in intermediate-risk prostate cancer. Radiother Oncol 2019; 133:16-19. [PMID: 30935573 DOI: 10.1016/j.radonc.2018.12.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 12/19/2018] [Accepted: 12/21/2018] [Indexed: 10/27/2022]
Abstract
Hypoxia is a major risk factor of prostate cancer radioresistance. We evaluated hypoxia non-invasively, using 18F-Misonidazole PET/CT prior to radiotherapy and after a dose of 20 Gy in intermediate-risk prostate cancer patients. Decreased hypoxic volumes were observed in all patients, suggesting that radiotherapy induces early prostate tumor reoxygenation.
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Affiliation(s)
- Stéphane Supiot
- Institut de Cancérologie de l'Ouest, Nantes-Saint Herblain, France; Centre de Recherche en Cancéro-Immunologie Nantes/Angers (CRCINA, UMR 892 INSERM), Institut de Recherche en Santé de l'Université de Nantes, Nantes CEDEX 1, France.
| | - Caroline Rousseau
- Institut de Cancérologie de l'Ouest, Nantes-Saint Herblain, France; Centre de Recherche en Cancéro-Immunologie Nantes/Angers (CRCINA, UMR 892 INSERM), Institut de Recherche en Santé de l'Université de Nantes, Nantes CEDEX 1, France
| | - Mélanie Dore
- Institut de Cancérologie de l'Ouest, Nantes-Saint Herblain, France; Centre de Recherche en Cancéro-Immunologie Nantes/Angers (CRCINA, UMR 892 INSERM), Institut de Recherche en Santé de l'Université de Nantes, Nantes CEDEX 1, France
| | | | | | - Vincent Potiron
- Institut de Cancérologie de l'Ouest, Nantes-Saint Herblain, France; Centre de Recherche en Cancéro-Immunologie Nantes/Angers (CRCINA, UMR 892 INSERM), Institut de Recherche en Santé de l'Université de Nantes, Nantes CEDEX 1, France
| | | | - François Paris
- Institut de Cancérologie de l'Ouest, Nantes-Saint Herblain, France; Centre de Recherche en Cancéro-Immunologie Nantes/Angers (CRCINA, UMR 892 INSERM), Institut de Recherche en Santé de l'Université de Nantes, Nantes CEDEX 1, France
| | - Ludovic Ferrer
- Institut de Cancérologie de l'Ouest, Nantes-Saint Herblain, France; Centre de Recherche en Cancéro-Immunologie Nantes/Angers (CRCINA, UMR 892 INSERM), Institut de Recherche en Santé de l'Université de Nantes, Nantes CEDEX 1, France
| | - Loïc Campion
- Institut de Cancérologie de l'Ouest, Nantes-Saint Herblain, France; Centre de Recherche en Cancéro-Immunologie Nantes/Angers (CRCINA, UMR 892 INSERM), Institut de Recherche en Santé de l'Université de Nantes, Nantes CEDEX 1, France
| | - Philippe Meingan
- Institut de Cancérologie de l'Ouest, Nantes-Saint Herblain, France
| | - Grégory Delpon
- Institut de Cancérologie de l'Ouest, Nantes-Saint Herblain, France; Centre de Recherche en Cancéro-Immunologie Nantes/Angers (CRCINA, UMR 892 INSERM), Institut de Recherche en Santé de l'Université de Nantes, Nantes CEDEX 1, France
| | - Mathieu Hatt
- Laboratoire de Traitement de l'Information Médicale (LATIM), INSERM, UMR 1101, Université de Bretagne Occidentale, IBSAM, faculté de médecine, 29238 Brest CEDEX, France
| | - Dimitris Visvikis
- Laboratoire de Traitement de l'Information Médicale (LATIM), INSERM, UMR 1101, Université de Bretagne Occidentale, IBSAM, faculté de médecine, 29238 Brest CEDEX, France
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13
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Wegener D, Zips D, Thorwarth D, Weiß J, Othman AE, Grosse U, Notohamiprodjo M, Nikolaou K, Müller AC. Precision of T2 TSE MRI-CT-image fusions based on gold fiducials and repetitive T2 TSE MRI-MRI-fusions for adaptive IGRT of prostate cancer by using phantom and patient data. Acta Oncol 2019; 58:88-94. [PMID: 30264629 DOI: 10.1080/0284186x.2018.1518594] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
INTRODUCTION To increase precision of radiation treatment (RT) delivery in prostate cancer, MRI-based RT as well as the use of fiducials like gold markers (GMs) have shown promising results. Their combined use is currently under investigation in clinical trials. Here, we aimed to evaluate a workflow of image registration based on GMs between CT and MRI as well as weekly MRI-MRI adaption based on T2 TSE sequence. MATERIAL AND METHODS A gel-phantom with two inserted GMs was scanned with CT and three different MR-scanners of 1.5 and 3 T (T2 TSE and T1 VIBE-Dixon, isotropic, voxel size 2 × 2 × 2 mm). After image fusion, deviations for fiducial and gel match were measured and artifacts were evaluated. Additionally, CT-MRI-match deviations and MRI-MRI-match deviations of 10 Patients from the M-basePro study using GMs were assessed. RESULTS GMs were visible in all imaging modalities. The outer gel contours were matched with <1 mm deviation, contour volumes varied between 0 and 1%. The deviations of the GMs were less than 2 mm in any direction of MRI/CT. Shifts of peripherally or centrally located GMs were randomly distributed. The average MRI-CT-match precision of 10 patients with GMs was 1.9 mm (range 1.1-3.1 mm). CONCLUSIONS Match inaccuracies for GMs between reference CT and voxel-isotropic T2-TSE sequences are small. Spatial deviations of CT- and MR-contoured fiducials were less than 2 mm, i.e., below SLT of the applied modalities. In patients, the average CT-MRI-match precision for GMs was 1.9 mm supporting their use in MR-guided high precision RT.
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Affiliation(s)
- D. Wegener
- Department of Radiation Oncology, University Hospital Tübingen, Eberhard Karls University Tübingen, Tübingen, Germany
| | - D. Zips
- Department of Radiation Oncology, University Hospital Tübingen, Eberhard Karls University Tübingen, Tübingen, Germany
- German Cancer Consortium (DKTK), Partner Site Tübingen; and German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - D. Thorwarth
- Section for Biomedical Physics, Department of Radiation Oncology, University Hospital Tübingen, Tübingen, Germany
- German Cancer Consortium (DKTK), Partner Site Tübingen; and German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - J. Weiß
- Department of Radiology, University Hospital Tübingen, Eberhard Karls University Tübingen, Tübingen, Germany
| | - A. E. Othman
- Department of Radiology, University Hospital Tübingen, Eberhard Karls University Tübingen, Tübingen, Germany
| | - U. Grosse
- Department of Radiology, University Hospital Tübingen, Eberhard Karls University Tübingen, Tübingen, Germany
| | - M. Notohamiprodjo
- Department of Radiology, University Hospital Tübingen, Eberhard Karls University Tübingen, Tübingen, Germany
| | - K. Nikolaou
- Department of Radiology, University Hospital Tübingen, Eberhard Karls University Tübingen, Tübingen, Germany
| | - A. C. Müller
- Department of Radiation Oncology, University Hospital Tübingen, Eberhard Karls University Tübingen, Tübingen, Germany
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14
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Nachbar M, Mönnich D, Kalwa P, Zips D, Thorwarth D, Gani C. Comparison of treatment plans for a high-field MRI-linac and a conventional linac for esophageal cancer. Strahlenther Onkol 2018; 195:327-334. [PMID: 30361744 DOI: 10.1007/s00066-018-1386-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 10/09/2018] [Indexed: 01/06/2023]
Abstract
PURPOSE To compare radiotherapy treatments plans in esophageal cancer calculated for a high-field magnetic resonance imaging (MRI)-linac with plans for a conventional linac. MATERIALS AND METHODS Ten patients with esophageal squamous cell carcinomas were re-planned retrospectively using the research version of Monaco (V 5.19.03, Elekta AB, Stockholm, Sweden). Intensity modulated radiotherapy (IMRT) plans with a nine-field step-and-shoot technique and two-arc volumetric modulated arc therapy (VMAT) plans were created for the Elekta MRI-linac and a conventional linac, respectively. The prescribed dose was 60 Gy to the primary tumor (PTV60) and 50 Gy to elective volumes (PTV50). Plans were optimized for optimal coverage of the 60 Gy volume and compared using dose-volume histogram parameters. RESULTS All calculated treatment plans met predefined criteria for target volume coverage and organs at risk dose both for MRI-linac and conventional linac. Plans for the MRI-linac had a lower number of segments and monitor units. No significant differences between both plans were seen in terms of V20Gy of the lungs and V40Gy of the heart with slightly higher mean doses to the heart (14.0 Gy vs. 12.5 Gy) and lungs (12.8 Gy vs. 12.2 Gy). CONCLUSION Applying conventional target volume and margin concepts as well as dose-fractionation prescription reveals clinically acceptable dose distributions using hybrid MRI-linac in its current configuration compared to standard IMRT/VMAT. This represents an important prerequisite for future studies to investigate the clinical benefit of MRI-guided radiotherapy exploiting the conceptional advantages such as reduced margins, plan adaptation and biological individualization and hypofractionation.
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Affiliation(s)
- Marcel Nachbar
- Section for Biomedical Physics, Department of Radiation Oncology, University Hospital and Medical Faculty, Eberhard Karls University Tübingen, Tübingen, Germany
| | - David Mönnich
- Section for Biomedical Physics, Department of Radiation Oncology, University Hospital and Medical Faculty, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Paul Kalwa
- Section for Biomedical Physics, Department of Radiation Oncology, University Hospital and Medical Faculty, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Daniel Zips
- German Cancer Consortium (DKTK), Partner Site Tübingen; and German Cancer Research Center (DKFZ), Heidelberg, Germany
- Department of Radiation Oncology, University Hospital and Medical Faculty, Eberhard Karls University Tübingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany
| | - Daniela Thorwarth
- Section for Biomedical Physics, Department of Radiation Oncology, University Hospital and Medical Faculty, Eberhard Karls University Tübingen, Tübingen, Germany
- German Cancer Consortium (DKTK), Partner Site Tübingen; and German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Cihan Gani
- German Cancer Consortium (DKTK), Partner Site Tübingen; and German Cancer Research Center (DKFZ), Heidelberg, Germany.
- Department of Radiation Oncology, University Hospital and Medical Faculty, Eberhard Karls University Tübingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany.
- Gastrointestinal Cancer Center, Comprehensive Cancer Center Tübingen-Stuttgart, Tübingen, Germany.
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15
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Bonnitcha P, Grieve S, Figtree G. Clinical imaging of hypoxia: Current status and future directions. Free Radic Biol Med 2018; 126:296-312. [PMID: 30130569 DOI: 10.1016/j.freeradbiomed.2018.08.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 07/30/2018] [Accepted: 08/14/2018] [Indexed: 12/20/2022]
Abstract
Tissue hypoxia is a key feature of many important causes of morbidity and mortality. In pathologies such as stroke, peripheral vascular disease and ischaemic heart disease, hypoxia is largely a consequence of low blood flow induced ischaemia, hence perfusion imaging is often used as a surrogate for hypoxia to guide clinical diagnosis and treatment. Importantly, ischaemia and hypoxia are not synonymous conditions as it is not universally true that well perfused tissues are normoxic or that poorly perfused tissues are hypoxic. In pathologies such as cancer, for instance, perfusion imaging and oxygen concentration are less well correlated, and oxygen concentration is independently correlated to radiotherapy response and overall treatment outcomes. In addition, the progression of many diseases is intricately related to maladaptive responses to the hypoxia itself. Thus there is potentially great clinical and scientific utility in direct measurements of tissue oxygenation. Despite this, imaging assessment of hypoxia in patients is rarely performed in clinical settings. This review summarises some of the current methods used to clinically evaluate hypoxia, the barriers to the routine use of these methods and the newer agents and techniques being explored for the assessment of hypoxia in pathological processes.
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Affiliation(s)
- Paul Bonnitcha
- Northern and Central Clinical Schools, Faculty of Medicine, Sydney University, Sydney, NSW 2006, Australia; Chemical Pathology Department, NSW Health Pathology, Royal Prince Alfred Hospital, Camperdown, NSW 2050, Australia; Kolling Institute of Medical Research, University of Sydney, St Leonards, New South Wales 2065, Australia.
| | - Stuart Grieve
- Sydney Translational Imaging Laboratory, Heart Research Institute, Charles Perkins Centre and Sydney Medical School, University of Sydney, NSW 2050, Australia
| | - Gemma Figtree
- Kolling Institute of Medical Research, University of Sydney, St Leonards, New South Wales 2065, Australia; Cardiology Department, Royal North Shore Hospital, St Leonards, New South Wales 2065, Australia
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16
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Brynolfsson P, Axelsson J, Holmberg A, Jonsson JH, Goldhaber D, Jian Y, Illerstam F, Engström M, Zackrisson B, Nyholm T. Technical Note: Adapting a GE SIGNA PET/MR scanner for radiotherapy. Med Phys 2018; 45:3546-3550. [PMID: 29862522 DOI: 10.1002/mp.13032] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 05/09/2018] [Accepted: 05/09/2018] [Indexed: 12/25/2022] Open
Abstract
PURPOSE Simultaneous collection of PET and MR data for radiotherapy purposes are useful for, for example, target definition and dose escalations. However, a prerequisite for using PET/MR in the radiotherapy workflow is the ability to image the patient in treatment position. The aim of this work was to adapt a GE SIGNA PET/MR scanner to image patients for radiotherapy treatment planning and evaluate the impact on signal-to-noise (SNR) of the MR images, and the accuracy of the PET attenuation correction. METHOD A flat tabletop and a coil holder were developed to image patients in the treatment position, avoid patient contour deformation, and facilitate attenuation correction of flex coils. Attenuation corrections for the developed hardware and an anterior array flex coil were also measured and implemented to the PET/MR system to minimize PET quantitation errors. The reduction of SNR in the MR images due to the added distance between the coils and the patient was evaluated using a large homogenous saline-doped water phantom, and the activity quantitation errors in PET imaging were evaluated with and without the developed attenuation corrections. RESULT We showed that the activity quantitation errors in PET imaging were within ±5% when correcting for attenuation of the flat tabletop, coil holder, and flex coil. The SNR of the MRI images were reduced to 74% using the tabletop, and 66% using the tabletop and coil holders. CONCLUSION We present a tabletop and coil holder for an anterior array coil to be used with a GE SIGNA PET/MR scanner, for scanning patients in the radiotherapy work flow. Implementing attenuation correction of the added hardware from the radiotherapy setup leads to acceptable PET image quantitation. The drop in SNR in MR images may require adjustment of the imaging protocols.
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Affiliation(s)
| | - Jan Axelsson
- Department of Radiation Sciences, Umeå University, Umeå, 901 87, Sweden
| | - August Holmberg
- Department of Radiation Sciences, Umeå University, Umeå, 901 87, Sweden
| | - Joakim H Jonsson
- Department of Radiation Sciences, Umeå University, Umeå, 901 87, Sweden
| | | | | | | | | | - Björn Zackrisson
- Department of Radiation Sciences, Umeå University, Umeå, 901 87, Sweden
| | - Tufve Nyholm
- Department of Radiation Sciences, Umeå University, Umeå, 901 87, Sweden
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17
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Zschaeck S, Lohaus F, Beck M, Habl G, Kroeze S, Zamboglou C, Koerber SA, Debus J, Hölscher T, Wust P, Ganswindt U, Baur ADJ, Zöphel K, Cihoric N, Guckenberger M, Combs SE, Grosu AL, Ghadjar P, Belka C. PSMA-PET based radiotherapy: a review of initial experiences, survey on current practice and future perspectives. Radiat Oncol 2018; 13:90. [PMID: 29751842 PMCID: PMC5948793 DOI: 10.1186/s13014-018-1047-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 05/08/2018] [Indexed: 01/05/2023] Open
Abstract
68Gallium prostate specific membrane antigen (PSMA) ligand positron emission tomography (PET) is an increasingly used imaging modality in prostate cancer, especially in cases of tumor recurrence after curative intended therapy. Owed to the novelty of the PSMA-targeting tracers, clinical evidence on the value of PSMA-PET is moderate but rapidly increasing. State of the art imaging is pivotal for radiotherapy treatment planning as it may affect dose prescription, target delineation and use of concomitant therapy. This review summarizes the evidence on PSMA-PET imaging from a radiation oncologist’s point of view. Additionally a short survey containing twelve examples of patients and 6 additional questions was performed in seven mayor academic centers with experience in PSMA ligand imaging and the findings are reported here.
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Affiliation(s)
- Sebastian Zschaeck
- Department of Radiation Oncology, Klinik für Radioonkologie und Strahlentherapie, Charité Universitätsmedizin Berlin, Berlin, Germany. .,Charité Universitätsmedizin Berlin, Klinik für Radioonkologie und Strahlentherapie, Augustenburger Platz 1, 13353, Berlin, Germany.
| | - Fabian Lohaus
- Department of Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,German Cancer Research Center (DKFZ), Heidelberg and German Cancer Consortium (DKTK), Dresden, Germany
| | - Marcus Beck
- Department of Radiation Oncology, Klinik für Radioonkologie und Strahlentherapie, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Gregor Habl
- Department of Radiation Oncology, Technical University of Munich (TUM), Munich, Germany.,Institute of Innovative Radiotherapy (iRT), Department of Radiation Sciences (DRS), Helmholtz Zentrum München (HMGU), München, Germany
| | - Stephanie Kroeze
- Department of Radiation Oncology, University Hospital Zurich, Zurich, Switzerland
| | - Constantinos Zamboglou
- Department of Radiation Oncology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Dresden, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, Dresden, Germany
| | - Stefan Alexander Koerber
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany.,German cancer research center (DKFZ) and german consortium for translational cancer research (DKTK), Heidelberg, Germany
| | - Jürgen Debus
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany.,German cancer research center (DKFZ) and german consortium for translational cancer research (DKTK), Heidelberg, Germany
| | - Tobias Hölscher
- Department of Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,German Cancer Research Center (DKFZ), Heidelberg and German Cancer Consortium (DKTK), Dresden, Germany
| | - Peter Wust
- Department of Radiation Oncology, Klinik für Radioonkologie und Strahlentherapie, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Ute Ganswindt
- Department of Therapeutic Radiology and Oncology, Innsbruck Medical University, Innsbruck, Austria
| | | | - Klaus Zöphel
- Nuclear Medicine Department, University Hospital Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - Nikola Cihoric
- Department of Radiation Oncology, Inselspital, Bern University Hospital, University of Bern, München, Switzerland
| | | | - Stephanie E Combs
- Department of Radiation Oncology, Technical University of Munich (TUM), Munich, Germany.,Institute of Innovative Radiotherapy (iRT), Department of Radiation Sciences (DRS), Helmholtz Zentrum München (HMGU), München, Germany.,German Cancer Research Center (DKFZ), Heidelberg and German Cancer Consortium (DKTK) partner site Munich, Munich, Germany
| | - Anca Ligia Grosu
- Department of Radiation Oncology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Dresden, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, Dresden, Germany
| | - Pirus Ghadjar
- Department of Radiation Oncology, Klinik für Radioonkologie und Strahlentherapie, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Claus Belka
- Department of Radiation Oncology, Ludwig-Maximilians-University, Munich, Germany.,German Cancer Research Center (DKFZ), Heidelberg and German Cancer Consortium (DKTK) partner site Munich, Munich, Germany
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18
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Gainey M, Carles M, Mix M, Meyer PT, Bock M, Grosu AL, Baltas D. Biological imaging for individualized therapy in radiation oncology: part I physical and technical aspects. Future Oncol 2018. [PMID: 29521520 DOI: 10.2217/fon-2017-0464] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Recently, there has been an increase in the imaging modalities available for radiotherapy planning and radiotherapy prognostic outcome: dual energy computed tomography (CT), dynamic contrast enhanced CT, dynamic contrast enhanced magnetic resonance imaging (MRI), diffusion-weighted MRI, positron emission tomography-CT, dynamic contrast enhanced ultrasound, MR spectroscopy and positron emission tomography-MR. These techniques enable more precise gross tumor volume definition than CT alone and moreover allow subvolumes within the gross tumor volume to be defined which may be given a boost dose or an individual voxelized dose prescription may be derived. With increased plan complexity care must be taken to immobilize the patient in an accurate and reproducible manner. Moreover the physical and technical limitations of the entire treatment planning chain need to be well characterized and understood, interdisciplinary collaboration ameliorated (physicians and physicists within nuclear medicine, radiology and radiotherapy) and image protocols standardized.
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Affiliation(s)
- Mark Gainey
- Department of Radiation Oncology, Faculty of Medicine, Medical Center, University of Freiburg, D-79106 Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DFKZ), Heidelberg, D-69120 Germany
| | - Montserrat Carles
- Department of Radiation Oncology, Faculty of Medicine, Medical Center, University of Freiburg, D-79106 Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DFKZ), Heidelberg, D-69120 Germany
| | - Michael Mix
- German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DFKZ), Heidelberg, D-69120 Germany.,Department of Nuclear Medicine, Faculty of Medicine, Medical Center, University of Freiburg, D-79106 Germany
| | - Philipp T Meyer
- German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DFKZ), Heidelberg, D-69120 Germany.,Department of Nuclear Medicine, Faculty of Medicine, Medical Center, University of Freiburg, D-79106 Germany
| | - Michael Bock
- German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DFKZ), Heidelberg, D-69120 Germany.,Radiology - Medical Physics, Department of Radiology, Faculty of Medicine, Medical Center, University of Freiburg, D-79106 Germany
| | - Anca-Ligia Grosu
- Department of Radiation Oncology, Faculty of Medicine, Medical Center, University of Freiburg, D-79106 Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DFKZ), Heidelberg, D-69120 Germany
| | - Dimos Baltas
- Department of Radiation Oncology, Faculty of Medicine, Medical Center, University of Freiburg, D-79106 Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center (DFKZ), Heidelberg, D-69120 Germany
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19
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Evaluation of tumor hypoxia prior to radiotherapy in intermediate-risk prostate cancer using 18F-fluoromisonidazole PET/CT: a pilot study. Oncotarget 2018. [PMID: 29515786 PMCID: PMC5839367 DOI: 10.18632/oncotarget.24234] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Purpose Hypoxia is a major factor in prostate cancer aggressiveness and radioresistance. Predicting which patients might be bad candidates for radiotherapy may help better personalize treatment decisions in intermediate-risk prostate cancer patients. We assessed spatial distribution of 18F-Misonidazole (FMISO) PET/CT uptake in the prostate prior to radiotherapy treatment. Materials and Methods Intermediate-risk prostate cancer patients about to receive high-dose (>74 Gy) radiotherapy to the prostate without hormonal treatment were prospectively recruited between 9/2012 and 10/2014. Prior to radiotherapy, all patients underwent a FMISO PET/CT as well as a MRI and 18F-choline-PET. 18F-choline and FMISO-positive volumes were semi-automatically determined using the fuzzy locally adaptive Bayesian (FLAB) method. In FMISO-positive patients, a dynamic analysis of early tumor uptake was performed. Group differences were assessed using the Wilcoxon signed rank test. Parameters were correlated using Spearman rank correlation. Results Of 27 patients (median age 76) recruited to the study, 7 and 9 patients were considered positive at 2.5h and 3.5h FMISO PET/CT respectively. Median SUVmax and SUVmax tumor to muscle (T/M) ratio were respectively 3.4 and 3.6 at 2.5h, and 3.2 and 4.4 at 3.5h. The median FMISO-positive volume was 1.1 ml. Conclusions This is the first study regarding hypoxia imaging using FMISO in prostate cancer showing that a small FMISO-positive volume was detected in one third of intermediate-risk prostate cancer patients.
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Kuess P, Andrzejewski P, Nilsson D, Georg P, Knoth J, Susani M, Trygg J, Helbich TH, Polanec SH, Georg D, Nyholm T. Association between pathology and texture features of multi parametric MRI of the prostate. ACTA ACUST UNITED AC 2017; 62:7833-7854. [DOI: 10.1088/1361-6560/aa884d] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Thorwarth D. Biologically adapted radiation therapy. Z Med Phys 2017; 28:177-183. [PMID: 28869163 DOI: 10.1016/j.zemedi.2017.08.001] [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: 05/24/2017] [Revised: 08/02/2017] [Accepted: 08/07/2017] [Indexed: 01/05/2023]
Abstract
The aim of biologically adapted radiotherapy (RT) is to shape or paint the prescribed radiation dose according to biological properties of the tumor in order to increase local control rates in the future. Human tumors are known to present with an extremely heterogeneous tissue architecture leading to highly variable local cell densities and chaotic vascular structures leading to tumor hypoxia and regions of increased radiation resistance. The goal of biologically adapted RT or dose painting is to individually adapt the radiation dose to biological features of the tumor as non-invasively assessed with functional imaging in order to overcome increased radiation resistance. This article discusses the whole development chain of biologically adapted RT from radio-biologically relevant processes, functional imaging techniques to visualize tumor biology non-invasively and radiation prescription functions to the implementation of biologically adapted RT in clinical practice.
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Affiliation(s)
- Daniela Thorwarth
- Sektion Biomedizinische Physik, Universitätsklinikum für Radioonkologie, Eberhard Karls Universität Tübingen, Germany.
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Modeling tumor control probability for spatially inhomogeneous risk of failure based on clinical outcome data. Z Med Phys 2017; 27:285-299. [PMID: 28676371 DOI: 10.1016/j.zemedi.2017.06.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2016] [Revised: 06/08/2017] [Accepted: 06/09/2017] [Indexed: 12/11/2022]
Abstract
PURPOSE Objectives of this work are (1) to derive a general clinically relevant approach to model tumor control probability (TCP) for spatially variable risk of failure and (2) to demonstrate its applicability by estimating TCP for patients planned for photon and proton irradiation. METHODS AND MATERIALS The approach divides the target volume into sub-volumes according to retrospectively observed spatial failure patterns. The product of all sub-volume TCPi values reproduces the observed TCP for the total tumor. The derived formalism provides for each target sub-volume i the tumor control dose (D50,i) and slope (γ50,i) parameters at 50% TCPi. For a simultaneous integrated boost (SIB) prescription for 45 advanced head and neck cancer patients, TCP values for photon and proton irradiation were calculated and compared. The target volume was divided into gross tumor volume (GTV), surrounding clinical target volume (CTV), and elective CTV (CTVE). The risk of a local failure in each of these sub-volumes was taken from the literature. RESULTS Convenient expressions for D50,i and γ50,i were provided for the Poisson and the logistic model. Comparable TCP estimates were obtained for photon and proton plans of the 45 patients using the sub-volume model, despite notably higher dose levels (on average +4.9%) in the low-risk CTVE for photon irradiation. In contrast, assuming a homogeneous dose response in the entire target volume resulted in TCP estimates contradicting clinical experience (the highest failure rate in the low-risk CTVE) and differing substantially between photon and proton irradiation. CONCLUSIONS The presented method is of practical value for three reasons: It (a) is based on empirical clinical outcome data; (b) can be applied to non-uniform dose prescriptions as well as different tumor entities and dose-response models; and (c) is provided in a convenient compact form. The approach may be utilized to target spatial patterns of local failures observed in patient cohorts by prescribing different doses to different target regions. Its predictive power depends on the uncertainty of the employed established TCP parameters D50 and γ50 and to a smaller extent on that of the clinically observed pattern of failure risk.
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Abedi I, Tavakkoli MB, Jabbari K, Amouheidari A, Yadegarfard G. Dosimetric and Radiobiological Evaluation of Multiparametric MRI-Guided Dose Painting in Radiotherapy of Prostate Cancer. JOURNAL OF MEDICAL SIGNALS AND SENSORS 2017; 7:114-121. [PMID: 28553585 PMCID: PMC5437763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Radiotherapy is one of the treatment options for locally advanced prostate cancer; however, with standard radiation doses, it is not always very effective. One of the strategies to improve the efficiency of radiotherapy is increasing the dose. In this study, to increase tumor local control rates, a new radiotherapy method, known as dose painting (DP), was investigated. To compare 3-dimensional conformal radiotherapy (3D-CRT) and intensity modulated radiotherapy (IMRT) plans with DP for prostate cancer. Twenty-four consecutive patients with locally advanced prostate cancer who underwent an multiparametric-magnetic resonance imaging (MP-MRI) (T2w, diffusion weighted image, dynamic contrast enhancement, and MRS) scan before a diagnostic biopsy from September 2015 to April 2016 were invited to take part in this study. The tumor local control probability (TCP) values for 3D-CRT, IMRT, and DP techniques were 45, 56, and 77%, respectively. The DP technique had a 37.5 and 71% higher TCP than IMRT and 3D-CRT, and these differences were statistically significant (P = 0.001). The mean normal tissue complication probability (NTCP) values of the organ at risks for 3D-CRT, IMRT, and DP showed that there were statistically significant differences among them in three plans (P = 0.01). DP by contours using MP-MRI is technically feasible. This study evaluated biological modeling based on both MP-MRI defined subvolumes and pathologically defined subvolumes. The MP-MRI-guided DP results in better TCP/NTCP than 3D-CRT and IMRT.
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Affiliation(s)
- Iraj Abedi
- Isfahan University of Medical Sciences, Isfahan, Iran
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Tavakkoli M, Abedi I, Jabbari K, Amouheidari A, Yadegarfard G. Dosimetric and Radiobiological Evaluation of Multiparametric MRI-Guided Dose Painting in Radiotherapy of Prostate Cancer. JOURNAL OF MEDICAL SIGNALS & SENSORS 2017. [DOI: 10.4103/2228-7477.205504] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Zamboglou C, Drendel V, Jilg CA, Rischke HC, Beck TI, Schultze-Seemann W, Krauss T, Mix M, Schiller F, Wetterauer U, Werner M, Langer M, Bock M, Meyer PT, Grosu AL. Comparison of 68Ga-HBED-CC PSMA-PET/CT and multiparametric MRI for gross tumour volume detection in patients with primary prostate cancer based on slice by slice comparison with histopathology. Am J Cancer Res 2017; 7:228-237. [PMID: 28042330 PMCID: PMC5196899 DOI: 10.7150/thno.16638] [Citation(s) in RCA: 122] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 09/11/2016] [Indexed: 02/07/2023] Open
Abstract
Purpose: The exact detection and delineation of the intraprostatic tumour burden is crucial for treatment planning in primary prostate cancer (PCa). We compared 68Ga-HBED-CC-PSMA PET/CT with multiparametric MRI (mpMRI) for diagnosis and tumour delineation in patients with primary PCa based on slice by slice correlation with histopathological reference material. Methodology: Seven patients with histopathologically proven primary PCa underwent 68Ga-HBED-CC-PSMA PET/CT and MRI followed by radical prostatectomy. Resected prostates were scanned by ex-vivo CT in a special localizer and prepared for histopathology. Invasive PCa was delineated on a HE stained histologic tissue slide and matched to ex-vivo CT to obtain gross tumor volume (GTV-)histo. Ex-vivo CT including GTV-histo and MRI data were matched to in-vivo CT(PET). Consensus contours based on MRI (GTV-MRI), PSMA PET (GTV-PET) or the combination of both (GTV-union/-intersection) were created. In each in-vivo CT slice the prostate was separated into 4 equal segments and sensitivity and specificity for PSMA PET and mpMRI were assessed by comparison with histological reference material. Furthermore, the spatial overlap between GTV-histo and GTV-PET/-MRI and the Sørensen-Dice coefficient (DSC) were calculated. In the case of multifocal PCa (4/7 patients), SUV values (PSMA PET) and ADC-values (diffusion weighted MRI) were obtained for each lesion. Results: PSMA PET and mpMRI detected PCa in all patients. GTV-histo was detected in 225 of 340 segments (66.2%). Sensitivity and specificity for GTV-PET, GTV-MRI, GTV-union and GTV-intersection were 75% and 87%, 70% and 82%, 82% and 67%, 55% and 99%, respectively. GTV-histo had on average the highest overlap with GTV-union (57±22%), which was significantly higher than overlap with GTV-MRI (p=0.016) and GTV-PET (p=0.016), respectively. The mean DSC for GTV-union, GTV-PET and GTV-MRI was 0.51 (±0.18), 0.45 (±0.17) and 0.48 (±0.19), respectively. In every patient with multifocal PCa there was one lesion which had both the highest SUV and the lowest ADC-value (mean and max). Conclusion: In a slice by slice analysis with histopathology, 68Ga-HBED-CC-PSMA PET/CT and mpMRI showed high sensitivity and specificity in detection of primary PCa. A combination of both methods performed even better in terms of sensitivity (GTV-union) and specificity (GTV-intersection). A moderate to good spatial overlap with GTV-histo was observed for PSMA PET/CT and mpMRI alone which was significantly improved by GTV-union. Further studies are warranted to analyse the impact of these preliminary findings for diagnostic (multimodal guided TRUS biopsy) and therapeutic (focal therapy) strategies in primary PCa.
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