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Sterpin E, Widesott L, Poels K, Hoogeman M, Korevaar EW, Lowe M, Molinelli S, Fracchiolla F. Robustness evaluation of pencil beam scanning proton therapy treatment planning: A systematic review. Radiother Oncol 2024; 197:110365. [PMID: 38830538 DOI: 10.1016/j.radonc.2024.110365] [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: 08/09/2023] [Revised: 04/30/2024] [Accepted: 05/29/2024] [Indexed: 06/05/2024]
Abstract
Compared to conventional radiotherapy using X-rays, proton therapy, in principle, allows better conformity of the dose distribution to target volumes, at the cost of greater sensitivity to physical, anatomical, and positioning uncertainties. Robust planning, both in terms of plan optimization and evaluation, has gained high visibility in publications on the subject and is part of clinical practice in many centers. However, there is currently no consensus on the methods and parameters to be used for robust optimization or robustness evaluation. We propose to overcome this deficiency by following the modified Delphi consensus method. This method first requires a systematic review of the literature. We performed this review using the PubMed and Web Of Science databases, via two different experts. Potential conflicts were resolved by a third expert. We then explored the different methods before focusing on clinical studies that evaluate robustness on a significant number of patients. Many robustness assessment methods are proposed in the literature. Some are more successful than others and their implementation varies between centers. Moreover, they are not all statistically or mathematically equivalent. The most sophisticated and rigorous methods have seen more limited application due to the difficulty of their implementation and their lack of widespread availability.
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Affiliation(s)
- E Sterpin
- KU Leuven - Department of Oncology, Laboratory of Experimental Radiotherapy, Leuven, Belgium; UCLouvain - Institution de Recherche Expérimentale et Clinique, Center of Molecular Imaging Radiotherapy and Oncology (MIRO), Brussels, Belgium; Particle Therapy Interuniversity Center Leuven - PARTICLE, Leuven, Belgium.
| | - L Widesott
- Proton Therapy Center - UO Fisica Sanitaria, Azienda Provinciale per i Servizi Sanitari (APSS), Trento, Italy
| | - K Poels
- Particle Therapy Interuniversity Center Leuven - PARTICLE, Leuven, Belgium; UZ Leuven, Department of Radiation Oncology, Leuven, Belgium
| | - M Hoogeman
- Erasmus Medical Center, Cancer Institute, Department of Radiotherapy, Rotterdam, the Netherlands; HollandPTC, Delft, the Netherlands
| | - E W Korevaar
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, the Netherlands
| | - M Lowe
- Christie Medical Physics and Engineering, The Christie NHS Foundation Trust, Manchester, UK
| | - S Molinelli
- Fondazione CNAO - Medical Physics Unit, Pavia, Italy
| | - F Fracchiolla
- Proton Therapy Center - UO Fisica Sanitaria, Azienda Provinciale per i Servizi Sanitari (APSS), Trento, Italy
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Dionisi F, Landoni V, Widesott L, Nardangeli A, Fracchiolla F, Siniscalchi B, Soriani A, Turkaj A, Righetto R, Amelio D, Farace P, Goanta L, Trianni A, Lorentini S, Cianchetti M, Sanguineti G. Dosimetric and NTCP advantages of robust proton therapy over robust VMAT for Stage III NSCLC in the immunotherapy era. Phys Med 2024; 123:103410. [PMID: 38878630 DOI: 10.1016/j.ejmp.2024.103410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 04/29/2024] [Accepted: 06/10/2024] [Indexed: 07/13/2024] Open
Abstract
AIMS To assess the robustness and to define the dosimetric and NTCP advantages of pencil-beam-scanning proton therapy (PBSPT) compared with VMAT for unresectable Stage III non-small lung cancer (NSCLC) in the immunotherapy era. MATERIAL AND METHODS 10 patients were re-planned with VMAT and PBSPT using: 1) ITV-based robust optimization with 0.5 cm setup uncertainties and (for PBSPT) 3.5 % range uncertainties on free-breathing CT 2) CTV-based RO including all 4DCTs anatomies. Target coverage (TC), organs at risk dose and TC robustness (TCR), set at V95%, were compared. The NTCP risk for radiation pneumonitis (RP), 24-month mortality (24MM), G2 + acute esophageal toxicity (ET), the dose to the immune system (EDIC) and the left anterior descending (LAD) coronary artery V15 < 10 % were registered. Wilcoxon test was used. RESULTS Both PBSPT methods improved TC and TCR (p < 0.01). The mean lung dose and lung V20 were lower with PBSPT (p < 0.01). Median mean heart dose reduction with PBSPT was 8 Gy (p < 0.001). PT lowered median LAD V15 (p = 0.004). ΔNTCP > 5 % with PBSPT was observed for two patients for RP and for five patients for 24 MM. ΔNTCP for ≥ G2 ET was not in favor of PBSPT for all patients. PBSPT halved median EDIC (4.9/5.1 Gy for ITV/CTV-based VMAT vs 2.3 Gy for both ITV/CTV-based PBSPT, p < 0.01). CONCLUSIONS PBSPT is a robust approach with significant dosimetric and NTCP advantages over VMAT; the EDIC reduction could allow for a better integration with immunotherapy. A clinical benefit for a subset of NSCLC patients is expected.
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Affiliation(s)
- F Dionisi
- Department of Research and Advanced Technology, Radiotherapy Unit, IRCCS Regina Elena National Cancer Institute-Rome, Italy.
| | - V Landoni
- Laboratory of Medical Physics and Expert Systems, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - L Widesott
- Medical Physics Department, APSS, Trento, Italy
| | - A Nardangeli
- Department of Research and Advanced Technology, Radiotherapy Unit, IRCCS Regina Elena National Cancer Institute-Rome, Italy
| | | | | | - A Soriani
- Laboratory of Medical Physics and Expert Systems, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - A Turkaj
- Proton Therapy Unit, APSS, Trento, Italy
| | - R Righetto
- Medical Physics Department, APSS, Trento, Italy
| | - D Amelio
- Proton Therapy Unit, APSS, Trento, Italy
| | - P Farace
- Medical Physics Department, APSS, Trento, Italy
| | - L Goanta
- Department of Research and Advanced Technology, Radiotherapy Unit, IRCCS Regina Elena National Cancer Institute-Rome, Italy
| | - A Trianni
- Medical Physics Department, APSS, Trento, Italy
| | - S Lorentini
- Medical Physics Department, APSS, Trento, Italy
| | | | - G Sanguineti
- Department of Research and Advanced Technology, Radiotherapy Unit, IRCCS Regina Elena National Cancer Institute-Rome, Italy
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Takaoka T, Yanagi T, Takahashi S, Shibamoto Y, Imai Y, Okazaki D, Niwa M, Torii A, Kita N, Takano S, Tomita N, Hiwatashi A. Comparing different boost concepts and beam configurations for proton therapy of pancreatic cancer. Phys Imaging Radiat Oncol 2024; 30:100583. [PMID: 38711921 PMCID: PMC11070341 DOI: 10.1016/j.phro.2024.100583] [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: 10/30/2023] [Revised: 04/26/2024] [Accepted: 04/26/2024] [Indexed: 05/08/2024] Open
Abstract
Background and Purpose Interfractional geometrical and anatomical variations impact the accuracy of proton therapy for pancreatic cancer. This study investigated field-in-field (FIF) and simultaneous integrated boost (SIB) concepts for scanned proton therapy treatment with different beam configurations. Materials and Methods Robustly optimized treatment plans for fifteen patients were generated using FIF and SIB techniques with two, three, and four beams. The prescribed dose in 20 fractions was 60 Gy(RBE) for the internal gross tumor volume (IGTV) and 46 Gy(RBE) for the internal clinical target volume. Verification computed tomography (vCT) scans was performed on treatment days 1, 7, and 16. Initial treatment plans were recalculated on the rigidly registered vCTs. V100% and D95% for targets and D2cm3 for the stomach and duodenum were evaluated. Robustness evaluations (range uncertainty of 3.5 %) were performed to evaluate the stomach and duodenum dose-volume parameters. Results For all techniques, IGTV V100% and D95% decreased significantly when recalculating the dose on vCTs (p < 0.001). The median IGTV V100% and D95% over all vCTs ranged from 74.2 % to 90.2 % and 58.8 Gy(RBE) to 59.4 Gy(RBE), respectively. The FIF with two and three beams, and SIB with two beams maintained the highest IGTV V100% and D95%. In robustness evaluations, the ΔD2cm3 of stomach was highest in two beams plans, while the ΔD2cm3 of duodenum was highest in four beams plans, for both concepts. Conclusion Target coverage decreased when recalculating on CTs at different time for both concepts. The FIF with three beams maintained the highest IGTV coverage while sparing normal organs the most.
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Affiliation(s)
- Taiki Takaoka
- Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Takeshi Yanagi
- Department of Radiation Oncology, Narita Memorial Proton Center, Toyohashi, Japan
| | - Shinsei Takahashi
- Department of Radiation Oncology, Narita Memorial Proton Center, Toyohashi, Japan
| | - Yuta Shibamoto
- Department of Radiation Oncology, Narita Memorial Proton Center, Toyohashi, Japan
| | - Yuto Imai
- Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
- Department of Radiation Oncology, Narita Memorial Proton Center, Toyohashi, Japan
| | - Dai Okazaki
- Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Masanari Niwa
- Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Akira Torii
- Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Nozomi Kita
- Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Seiya Takano
- Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Natsuo Tomita
- Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Akio Hiwatashi
- Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
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Tominaga Y, Suga M, Takeda M, Yamamoto Y, Akagi T, Kato T, Tokumaru S, Yamamoto M, Oita M. Comparing interplay effects in scanned proton therapy of lung cancer: Free breathing with various layer and volume rescanning versus respiratory gating with different gate widths. Phys Med 2024; 120:103323. [PMID: 38461635 DOI: 10.1016/j.ejmp.2024.103323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 02/07/2024] [Accepted: 03/04/2024] [Indexed: 03/12/2024] Open
Abstract
PURPOSE We investigated interplay effects and treatment time (TT) in scanned proton therapy for lung cancer patients. We compared free-breathing (FB) approaches with multiple rescanning strategies and respiratory-gating (RG) methods with various gating widths to identify the superior irradiation technique. METHODS Plans were created with 4/1, 2/2, and 1/4 layered/volume rescans of FB (L4V1, L2V2, and L1V4), and 50%, 30%, and 10% gating widths of the total respiratory curves (G50, G30, and G10) of the RG plans with L4V1. We calculated 4-dimensional dynamic doses assuming a constant sinusoidal curve for six irradiation methods. The reconstructed doses per fraction were compared with planned doses in terms of dose differences in 99% clinical-target-volume (CTV) (ΔD99%), near-maximum dose differences (ΔD2%) at organs-at-risk (OARs), and TT. RESULTS The mean/minimum CTV ΔD99% values for FB were -1.0%/-4.9%, -0.8%/-4.3%, and -0.1%/-1.0% for L4V1, L2V2, and L1V4, respectively. Those for RG were -0.3%/-1.7%, -0.1%/-1.0%, and 0.0%/-0.5% for G50, G30, and G10, respectively. The CTV ΔD99% of the RGs with less than 50% gate width and the FBs of L1V4 were within the desired tolerance (±3.0%), and the OARs ΔD2% for RG were lower than those for FB. The mean TTs were 90, 326, 824, 158, 203, and 422 s for L4V1, L2V2, L1V4, G50, G30, and G10, respectively. CONCLUSIONS FB (L4V1) is the most efficient treatment, but not necessarily the optimal choice due to interplay effects. To satisfy both TT extensions and interplay, RG with a gate width as large as possible within safety limits is desirable.
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Affiliation(s)
- Yuki Tominaga
- Department of Radiotherapy, Medical Co. Hakuhokai, Osaka Proton Therapy Clinic, 27-9 Kasugadenaka, Konohana-ku, Osaka 554-0022, Japan.
| | - Masaki Suga
- Hyogo Ion Beam Medical Center, 1-2-1, Kouto, Shingucho, Tatsuno, Hyogo 679-5165, Japan
| | - Mikuni Takeda
- Hyogo Ion Beam Medical Center, 1-2-1, Kouto, Shingucho, Tatsuno, Hyogo 679-5165, Japan
| | - Yuki Yamamoto
- Hyogo Ion Beam Medical Center, 1-2-1, Kouto, Shingucho, Tatsuno, Hyogo 679-5165, Japan
| | - Takashi Akagi
- Hyogo Ion Beam Medical Support, 1-2-1, Kouto, Shingucho, Tatsuno, Hyogo 679-5165, Japan
| | - Takahiro Kato
- Department of Radiological Sciences, School of Health Sciences, Fukushima Medical University, 1 Hikariga-oka, Fukushima 960-1295, Japan; Department of Radiation Physics and Technology, Southern Tohoku Proton Therapy Center, Fukushima 172, Yatsuyamada 7 Chome, Koriyama, Fukushima 963-8052, Japan
| | - Sunao Tokumaru
- Hyogo Ion Beam Medical Center, 1-2-1, Kouto, Shingucho, Tatsuno, Hyogo 679-5165, Japan
| | - Michinori Yamamoto
- Department of Radiotherapy, Medical Co. Hakuhokai, Osaka Proton Therapy Clinic, 27-9 Kasugadenaka, Konohana-ku, Osaka 554-0022, Japan
| | - Masataka Oita
- Faculty of Interdisciplinary Science and Engineering in Health Systems, Okayama University, 5-1 Shikata-cho, 2-chome, Kita-ku, Okayama 700-8558, Japan
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Daartz J, Madden TM, Lalonde A, Cascio E, Verburg J, Shih H, MacDonald S, Hachadorian R, Schuemann J. Voxel-wise dose rate calculation in clinical pencil beam scanning proton therapy. Phys Med Biol 2024; 69:065003. [PMID: 38324902 DOI: 10.1088/1361-6560/ad2713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 02/07/2024] [Indexed: 02/09/2024]
Abstract
Objective. Clinical outcomes after proton therapy have shown some variability that is not fully understood. Different approaches have been suggested to explain the biological outcome, but none has yet provided a comprehensive and satisfactory rationale for observed toxicities. The relatively recent transition from passive scattering (PS) to pencil beam scanning (PBS) treatments has significantly increased the voxel-wise dose rate in proton therapy. In addition, the dose rate distribution is no longer uniform along the cross section of the target but rather highly heterogeneous, following the spot placement. We suggest investigating dose rate as potential contributor to a more complex proton RBE model.Approach. Due to the time structure of the PBS beam delivery the instantaneous dose rate is highly variable voxel by voxel. Several possible parameters to represent voxel-wise dose rate for a given clinical PBS treatment plan are detailed. These quantities were implemented in the scripting environment of our treatment planning system, and computations experimentally verified. Sample applications to treated patient plans are shown.Main results. Computed dose rates we experimentally confirmed. Dose rate maps vary depending on which method is used to represent them. Mainly, the underlying time and dose intervals chosen determine the topography of the resultant distributions. The maximum dose rates experienced by any target voxel in a given PBS treatment plan in our system range from ∼100 to ∼450 Gy(RBE)/min, a factor of 10-100 increase compared to PS. These dose rate distributions are very heterogeneous, with distinct hot spots.Significance. Voxel-wise dose rates for current clinical PBS treatment plans vary greatly from clinically established practice with PS. The exploration of different dose rate measures to evaluate potential correlations with observed clinical outcomes is suggested, potentially adding a missing component in the understanding of proton relative biological effectiveness (RBE).
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Affiliation(s)
- Juliane Daartz
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA, United States of America
| | - Thomas M Madden
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA, United States of America
| | - Arthur Lalonde
- Centre Hospitalier de l'Université de Montréal, Montréal, Canada
| | - Ethan Cascio
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA, United States of America
| | - Joost Verburg
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA, United States of America
| | - Helen Shih
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA, United States of America
| | - Shannon MacDonald
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA, United States of America
| | - Rachael Hachadorian
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA, United States of America
| | - Jan Schuemann
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA, United States of America
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Knäusl B, Belotti G, Bertholet J, Daartz J, Flampouri S, Hoogeman M, Knopf AC, Lin H, Moerman A, Paganelli C, Rucinski A, Schulte R, Shimizu S, Stützer K, Zhang X, Zhang Y, Czerska K. A review of the clinical introduction of 4D particle therapy research concepts. Phys Imaging Radiat Oncol 2024; 29:100535. [PMID: 38298885 PMCID: PMC10828898 DOI: 10.1016/j.phro.2024.100535] [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: 10/11/2023] [Revised: 12/12/2023] [Accepted: 01/04/2024] [Indexed: 02/02/2024] Open
Abstract
Background and purpose Many 4D particle therapy research concepts have been recently translated into clinics, however, remaining substantial differences depend on the indication and institute-related aspects. This work aims to summarise current state-of-the-art 4D particle therapy technology and outline a roadmap for future research and developments. Material and methods This review focused on the clinical implementation of 4D approaches for imaging, treatment planning, delivery and evaluation based on the 2021 and 2022 4D Treatment Workshops for Particle Therapy as well as a review of the most recent surveys, guidelines and scientific papers dedicated to this topic. Results Available technological capabilities for motion surveillance and compensation determined the course of each 4D particle treatment. 4D motion management, delivery techniques and strategies including imaging were diverse and depended on many factors. These included aspects of motion amplitude, tumour location, as well as accelerator technology driving the necessity of centre-specific dosimetric validation. Novel methodologies for X-ray based image processing and MRI for real-time tumour tracking and motion management were shown to have a large potential for online and offline adaptation schemes compensating for potential anatomical changes over the treatment course. The latest research developments were dominated by particle imaging, artificial intelligence methods and FLASH adding another level of complexity but also opportunities in the context of 4D treatments. Conclusion This review showed that the rapid technological advances in radiation oncology together with the available intrafractional motion management and adaptive strategies paved the way towards clinical implementation.
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Affiliation(s)
- Barbara Knäusl
- Department of Radiation Oncology, Medical University of Vienna, Vienna, Austria
| | - Gabriele Belotti
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milano, Italy
| | - Jenny Bertholet
- Division of Medical Radiation Physics and Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern, Bern, Switzerland
| | - Juliane Daartz
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | | | - Mischa Hoogeman
- Department of Medical Physics & Informatics, HollandPTC, Delft, The Netherlands
- Erasmus MC Cancer Institute, University Medical Center Rotterdam, Department of Radiotherapy, Rotterdam, The Netherlands
| | - Antje C Knopf
- Institut für Medizintechnik und Medizininformatik Hochschule für Life Sciences FHNW, Muttenz, Switzerland
| | - Haibo Lin
- New York Proton Center, New York, NY, USA
| | - Astrid Moerman
- Department of Medical Physics & Informatics, HollandPTC, Delft, The Netherlands
| | - Chiara Paganelli
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milano, Italy
| | - Antoni Rucinski
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342 Krakow, Poland
| | - Reinhard Schulte
- Division of Biomedical Engineering Sciences, School of Medicine, Loma Linda University
| | - Shing Shimizu
- Department of Carbon Ion Radiotherapy, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Kristin Stützer
- OncoRay – National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
- Helmholtz-Zentrum Dresden – Rossendorf, Institute of Radiooncology – OncoRay, Dresden, Germany
| | - Xiaodong Zhang
- Department of Radiation Physics, Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Ye Zhang
- Center for Proton Therapy, Paul Scherrer Institute, Villigen PSI, Switzerland
| | - Katarzyna Czerska
- Center for Proton Therapy, Paul Scherrer Institute, Villigen PSI, Switzerland
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Spautz S, Haase L, Tschiche M, Makocki S, Richter C, Troost EG, Stützer K. Comparison of 3D and 4D robustly optimized proton treatment plans for non-small cell lung cancer patients with tumour motion amplitudes larger than 5 mm. Phys Imaging Radiat Oncol 2023; 27:100465. [PMID: 37449022 PMCID: PMC10338142 DOI: 10.1016/j.phro.2023.100465] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 06/22/2023] [Accepted: 06/23/2023] [Indexed: 07/18/2023] Open
Abstract
Background and purpose There is no consensus about an ideal robust optimization (RO) strategy for proton therapy of targets with large intrafractional motion. We investigated the plan robustness of 3D and different 4D RO strategies. Materials and methods For eight non-small cell lung cancer patients with clinical target volume (CTV) motion >5 mm, different RO approaches were investigated: 3DRO considering the average CT (AvgCT) with a target density override, 4DRO considering three/all 4DCT phases, and 4DRO considering the AvgCT and three/all 4DCT phases. Robustness against setup/range errors, interplay effects based on breathing and machine log file data for deliveries with/without rescanning, and interfractional anatomical changes were analyzed for target coverage and OAR sparing. Results All nominal plans fulfilled the clinical requirements with individual CTV coverage differences <2pp; 4DRO without AvgCT generated the most conformal dose distributions. Robustness against setup/range errors was best for 4DRO with AvgCT (18% more passed error scenarios than 3DRO). Interplay effects caused fraction-wise median CTV coverage loss of 3pp and missed maximum dose constraints for heart and esophagus in 18% of scenarios. CTV coverage and OAR sparing fulfilled requirements in all cases when accumulating four interplay scenarios. Interfractional changes caused less target misses for RO with AvgCT compared to 4DRO without AvgCT (≤42%/33% vs. ≥56%/44% failed single/accumulated scenarios). Conclusions All RO strategies provided acceptable plans with equally low robustness against interplay effects demanding other mitigation than rescanning to ensure fraction-wise target coverage. 4DRO considering three phases and the AvgCT provided best compromise on planning effort and robustness.
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Affiliation(s)
- Saskia Spautz
- OncoRay – National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden, Rossendorf, Fetscherstraße 74, PF 41, 01307 Dresden, Germany
| | - Leon Haase
- OncoRay – National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden, Rossendorf, Fetscherstraße 74, PF 41, 01307 Dresden, Germany
| | - Maria Tschiche
- Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, PF 50, 01307 Dresden, Germany
| | - Sebastian Makocki
- Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, PF 50, 01307 Dresden, Germany
| | - Christian Richter
- OncoRay – National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden, Rossendorf, Fetscherstraße 74, PF 41, 01307 Dresden, Germany
- Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, PF 50, 01307 Dresden, Germany
- Helmholtz-Zentrum Dresden – Rossendorf, Institute of Radiooncology – OncoRay, Bautzner Landstraße 400, 01328 Dresden, Germany
- German Cancer Consortium (DKTK), Partner Site Dresden, and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69192 Heidelberg, Germany
| | - Esther G.C. Troost
- OncoRay – National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden, Rossendorf, Fetscherstraße 74, PF 41, 01307 Dresden, Germany
- Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, PF 50, 01307 Dresden, Germany
- Helmholtz-Zentrum Dresden – Rossendorf, Institute of Radiooncology – OncoRay, Bautzner Landstraße 400, 01328 Dresden, Germany
- German Cancer Consortium (DKTK), Partner Site Dresden, and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69192 Heidelberg, Germany
- National Center for Tumor Diseases (NCT), Partner Site Dresden, Germany: German Cancer Research Center (DKFZ), Heidelberg, Germany; Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany, and; Helmholtz Association / Helmholtz-Zentrum Dresden - Rossendorf (HZDR), Dresden, Germany; Im Neuenheimer Feld 280, 69192 Heidelberg, Germany
| | - Kristin Stützer
- OncoRay – National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden, Rossendorf, Fetscherstraße 74, PF 41, 01307 Dresden, Germany
- Helmholtz-Zentrum Dresden – Rossendorf, Institute of Radiooncology – OncoRay, Bautzner Landstraße 400, 01328 Dresden, Germany
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Zhang Y, Trnkova P, Toshito T, Heijmen B, Richter C, Aznar M, Albertini F, Bolsi A, Daartz J, Bertholet J, Knopf A. A survey of practice patterns for real-time intrafractional motion-management in particle therapy. Phys Imaging Radiat Oncol 2023; 26:100439. [PMID: 37124167 PMCID: PMC10133874 DOI: 10.1016/j.phro.2023.100439] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 04/05/2023] [Accepted: 04/06/2023] [Indexed: 05/02/2023] Open
Abstract
Background and purpose Organ motion compromises accurate particle therapy delivery. This study reports on the practice patterns for real-time intrafractional motion-management in particle therapy to evaluate current clinical practice and wishes and barriers to implementation. Materials and methods An institutional questionnaire was distributed to particle therapy centres worldwide (7/2020-6/2021) asking which type(s) of real-time respiratory motion management (RRMM) methods were used, for which treatment sites, and what were the wishes and barriers to implementation. This was followed by a three-round DELPHI consensus analysis (10/2022) to define recommendations on required actions and future vision. With 70 responses from 17 countries, response rate was 100% for Europe (23/23 centres), 96% for Japan (22/23) and 53% for USA (20/38). Results Of the 68 clinically operational centres, 85% used RRMM, with 41% using both rescanning and active methods. Sixty-four percent used active-RRMM for at least one treatment site, mostly with gating guided by an external marker. Forty-eight percent of active-RRMM users wished to expand or change their RRMM technique. The main barriers were technical limitations and limited resources. From the DELPHI analysis, optimisation of rescanning parameters, improvement of motion models, and pre-treatment 4D evaluation were unanimously considered clinically important future focus. 4D dose calculation was identified as the top requirement for future commercial treatment planning software. Conclusion A majority of particle therapy centres have implemented RRMM. Still, further development and clinical integration were desired by most centres. Joint industry, clinical and research efforts are needed to translate innovation into efficient workflows for broad-scale implementation.
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Affiliation(s)
- Ye Zhang
- Center for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland
| | - Petra Trnkova
- Department of Radiation Oncology, Medical University of Vienna, Vienna, Austria
| | - Toshiyuki Toshito
- Nagoya Proton Therapy Center, Nagoya City University West Medical Center, Nagoya, Japan
| | - Ben Heijmen
- Department of Radiotherapy, Erasmus University Medical Center (Erasmus MC), Rotterdam, the Netherlands
| | - Christian Richter
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany
| | - Marianne Aznar
- Faculty of Biology, Medicine and Health, Division of Cancer Sciences, University of Manchester, United Kingdom
| | | | - Alexandra Bolsi
- Center for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland
| | - Juliane Daartz
- F. Burr Proton Therapy, Massachusetts General Hospital and Harvard Medical School, Boston, USA
| | - Jenny Bertholet
- Division of Medical Radiation Physics and Department of Radiation Oncology, Inselspital, Bern University Hospital, Bern, Switzerland
| | - Antje Knopf
- Center for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland
- Institute for Medical Engineering and Medical Informatics, School of Life Science FHNW, Muttenz, Switzerland
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9
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Clinical 3D/4D cumulative proton dose assessment methods for thoracic tumours with large motion. Radiother Oncol 2023; 182:109575. [PMID: 36822356 DOI: 10.1016/j.radonc.2023.109575] [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: 11/30/2022] [Revised: 01/31/2023] [Accepted: 02/12/2023] [Indexed: 02/25/2023]
Abstract
PURPOSE Despite the anticipated clinical benefits of intensity-modulated proton therapy (IMPT), plan robustness may be compromised due to its sensitivity to patient treatment uncertainties, especially for tumours with large motion. In this study, we investigated treatment course-wise plan robustness for intra-thoracic tumours with large motion comparing a 4D pre-clinical evaluation method (4DREM) to our clinical 3D/4D dose reconstruction and accumulation methods. MATERIALS AND METHODS Twenty patients with large target motion (>10 mm) were treated with five times layered rescanned IMPT. The 3D-robust optimised plans were generated on the averaged planning 4DCT. Using multiple 4DCTs, treatment plan robustness was assessed on a weekly and treatment course-wise basis through the 3D robustness evaluation method (3DREM, based on averaged 4DCTs), the 4D robustness evaluation method (4DREM, including the time structure of treatment delivery and 4DCT phases) and 4D dose reconstruction and accumulation (4DREAL, based on fraction-wise information). RESULTS Baseline target motion for all patients ranged from 11-17 mm. For the offline adapted course-wise dose assessment, adequate target dose coverage was found for all patients. The target volume receiving 95% of the prescription dose was consistent between methods with 16/20 patients showing differences < 1%. 4DREAL showed the highest target coverage (99.8 ± 0.6%, p < 0.001), while no differences were observed between 3DREM and 4DREM (99.3 ± 1.3% and 99.4 ± 1.1%, respectively). CONCLUSION Our results show that intra-thoracic tumours can be adequately treated with IMPT in free breathing for target motion amplitudes up to 17 mm employing any of the accumulation methods. Anatomical changes, setup and range errors demonstrated a more severe impact on target coverage than motion in these patients treated with fractionated proton radiotherapy.
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10
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Zaki P, Chuong MD, Schaub SK, Lo SS, Ibrahim M, Apisarnthanarax S. Proton Beam Therapy and Photon-Based Magnetic Resonance Image-Guided Radiation Therapy: The Next Frontiers of Radiation Therapy for Hepatocellular Carcinoma. Technol Cancer Res Treat 2023; 22:15330338231206335. [PMID: 37908130 PMCID: PMC10621304 DOI: 10.1177/15330338231206335] [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: 08/17/2022] [Revised: 08/21/2023] [Accepted: 09/21/2023] [Indexed: 11/02/2023] Open
Abstract
External beam radiation therapy (EBRT) has increasingly been utilized in the treatment of hepatocellular carcinoma (HCC) due to technological advances with positive clinical outcomes. Innovations in EBRT include improved image guidance, motion management, treatment planning, and highly conformal techniques such as intensity-modulated radiation therapy (IMRT) and stereotactic body radiation therapy (SBRT). Moreover, proton beam therapy (PBT) and magnetic resonance image-guided radiation therapy (MRgRT) have expanded the capabilities of EBRT. PBT offers the advantage of minimizing low- and moderate-dose radiation to the surrounding normal tissue, thereby preserving uninvolved liver and allowing for dose escalation. MRgRT provides the advantage of improved soft tissue delineation compared to computerized tomography (CT) guidance. Additionally, MRgRT with online adaptive therapy is particularly useful for addressing motion not otherwise managed and reducing high-dose radiation to the normal tissue such as the stomach and bowel. PBT and online adaptive MRgRT are emerging technological advancements in EBRT that may provide a significant clinical benefit for patients with HCC.
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Affiliation(s)
- Peter Zaki
- Department of Radiation Oncology, University of Washington, Seattle, WA, USA
| | - Michael D. Chuong
- Department of Radiation Oncology, Miami Cancer Institute, Miami, FL, USA
| | - Stephanie K. Schaub
- Department of Radiation Oncology, University of Washington, Seattle, WA, USA
| | - Simon S. Lo
- Department of Radiation Oncology, University of Washington, Seattle, WA, USA
| | - Mariam Ibrahim
- School of Medicine, St. George's University, St. George's, Grenada
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11
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Solidum JGN, Rojo RD, Wo JY, Dee EC. Proton Beam Therapy for Esophageal Cancer. Cancers (Basel) 2022; 14:cancers14164045. [PMID: 36011037 PMCID: PMC9407004 DOI: 10.3390/cancers14164045] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 08/09/2022] [Accepted: 08/12/2022] [Indexed: 12/05/2022] Open
Abstract
Simple Summary Early-stage esophageal cancer is managed surgically, with the addition of radiotherapy for locally advanced disease. Current photon-based radiotherapy results in a high treatment-related complications, due to proximal organ involvement. The anatomic location of the esophagus raises challenges due to the anatomical changes associated with diaphragmatic motion, weight loss, tumor changes, and set-up variability. These propelled the interest in proton beam therapy (PBT), which theoretically offers a reduction in the radiation exposure to healthy neighboring tissues with improvements in the therapeutic ratio. In this review, we present the role of PBT for esophageal cancer, including treatment planning, early clinical comparisons with photon-based techniques, ongoing trials, current challenges, toxicities, and issues of equity and health services. Abstract Early-stage esophageal cancer is often primarily managed surgically, with the addition of radiotherapy for locally advanced disease. However, current photon-based radiotherapy regimens and surgery results in a high incidence of treatment-related cardiac and pulmonary complications due to the involvement of proximal organs at risk. In addition, the anatomic location of the esophagus raises challenges for radiotherapy due to the anatomical changes associated with diaphragmatic motion, weight loss, tumor changes, and set-up variability. These challenges propelled the interest in proton beam therapy (PBT), which theoretically offers a reduction in the radiation exposure to healthy neighboring tissues with improvements in the therapeutic ratio. Several dosimetric studies support the potential advantages of PBT for esophageal cancer treatment however, translation of these results to improved clinical outcomes remains unclear with limited clinical data, especially in large populations. Studies on the effect on quality of life are likewise lacking. Here, we review the existing and emerging role of PBT for esophageal cancer, including treatment planning, early clinical comparisons of PBT with photon-based techniques, recently concluded and ongoing clinical trials, challenges and toxicities, effects on quality of life, and global inequities in the treatment of esophageal cancer.
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Affiliation(s)
- Jea Giezl N. Solidum
- College of Medicine, University of the Philippines Manila, Manila 1000, Metro Manila, Philippines
| | - Raniv D. Rojo
- College of Medicine, University of the Philippines Manila, Manila 1000, Metro Manila, Philippines
| | - Jennifer Y. Wo
- Department of Radiation Oncology, Massachusetts General Hospital, 100 Blossom St., Boston, MA 02114, USA
- Harvard Medical School, Boston, MA 02115, USA
| | - Edward Christopher Dee
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
- Correspondence:
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12
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Dionisi F, Scartoni D, Fracchiolla F, Giacomelli I, Siniscalchi B, Goanta L, Cianchetti M, Sanguineti G, Brolese A. Proton therapy in the treatment of hepatocellular carcinoma. Front Oncol 2022; 12:959552. [PMID: 36003769 PMCID: PMC9393743 DOI: 10.3389/fonc.2022.959552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 07/13/2022] [Indexed: 12/24/2022] Open
Abstract
Liver cancer represents one of the most common causes of death from cancer worldwide. Hepatocellular carcinoma (HCC) accounts for 90% of all primary liver cancers. Among local therapies, evidence regarding the use of radiation therapy is growing. Proton therapy currently represents the most advanced radiation therapy technique with unique physical properties which fit well with liver irradiation. Here, in this review, we aim to 1) illustrate the rationale for the use of proton therapy (PT) in the treatment of HCC, 2) discuss the technical challenges of advanced PT in this disease, 3) review the major clinical studies regarding the use of PT for HCC, and 4) analyze the potential developments and future directions of PT in this setting.
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Affiliation(s)
- Francesco Dionisi
- Department of Radiation Oncology, IRCCS Regina Elena National Cancer Institute, Rome, Italy
- *Correspondence: Francesco Dionisi,
| | - Daniele Scartoni
- Proton Therapy Unit, Azienda Provinciale per i Servizi Sanitari, Trento, Italy
| | | | - Irene Giacomelli
- Proton Therapy Unit, Azienda Provinciale per i Servizi Sanitari, Trento, Italy
| | | | - Lucia Goanta
- Department of Advanced Biomedical Sciences, University of Naples “Federico II”, Napoli, Italy
| | - Marco Cianchetti
- Proton Therapy Unit, Azienda Provinciale per i Servizi Sanitari, Trento, Italy
| | - Giuseppe Sanguineti
- Department of Radiation Oncology, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Alberto Brolese
- General Surgery & Hepato-Pancreato-Biliary Unit, Azienda Provinciale per i Servizi Sanitari, Trento, Italy
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13
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Spautz S, Jakobi A, Meijers A, Peters N, Löck S, Knopf AC, Troost EGC, Richter C, Stützer K. Experimental validation of 4D log file-based proton dose reconstruction for interplay assessment considering amplitude-sorted 4DCTs. Med Phys 2022; 49:3538-3549. [PMID: 35342943 DOI: 10.1002/mp.15625] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 02/01/2022] [Accepted: 03/13/2022] [Indexed: 11/06/2022] Open
Abstract
PURPOSE The unpredictable interplay between dynamic proton therapy delivery and target motion in the thorax can lead to severe dose distortions. A fraction-wise four-dimensional (4D) dose reconstruction workflow allows for the assessment of the applied dose after patient treatment while considering the actual beam delivery sequence extracted from machine log files, the recorded breathing pattern and the geometric information from a 4D computed tomography scan (4DCT). Such an algorithm capable of accounting for amplitude-sorted 4DCTs was implemented and its accuracy as well as its sensitivity to input parameter variations was experimentally evaluated. METHODS An anthropomorphic thorax phantom with a movable insert containing a target surrogate and a radiochromic film was irradiated with a monoenergetic field for various 1D target motion forms (sin, sin4) and peak-to-peak amplitudes (5/10/15/20/30 mm). The measured characteristic film dose distributions were compared to the respective sections in the 4D reconstructed doses using a 2D γ-analysis (3mm, 3%); γ-pass rates were derived for different dose grid resolutions (1mm/3mm) and deformable image registrations (DIR, automatic/manual) applied during the 4D dose reconstruction process. In an additional analysis, the sensitivity of reconstructed dose distributions against potential asynchronous timing of the motion and machine log files was investigated for both a monoenergetic field and more realistic 4D robustly optimized fields by artificially introduced offsets of ± 1/5/25/50/250 ms. The resulting dose distributions with asynchronized log files were compared to those with synchronized log files by means of a 3D γ-analysis (1mm, 1%) and the evaluation of absolute dose differences. RESULTS The induced characteristic interplay patterns on the films were well reproduced by the 4D dose reconstruction with 2D γ-pass rates ≥95% for almost all cases with motion magnitudes ≤15 mm. In general, the 2D γ-pass rates showed a significant decrease for larger motion amplitudes and increase when using a finer dose grid resolution but were not affected by the choice of motion form (sin, sin4). There was also a trend, though not statistically significant, towards the manually defined DIR for better quality of the reconstructed dose distributions in the area imaged by the film. The 4D dose reconstruction results for the monoenergetic as well as the 4D robustly optimized fields were robust against small asynchronies between motion and machine log files of up to 5 ms, which is in the order of potential network latencies. CONCLUSIONS We have implemented a 4D log file-based proton dose reconstruction that accounts for amplitude-sorted 4DCTs. Its accuracy was proven to be clinically acceptable for target motion magnitudes of up to 15 mm. Particular attention should be paid to the synchronization of the log file generating systems as the reconstructed dose distribution may vary with log file asynchronies larger than those caused by realistic network delays. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Saskia Spautz
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany
| | - Annika Jakobi
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany.,Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Dresden, Germany.,Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Arturs Meijers
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Nils Peters
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany.,Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Dresden, Germany
| | - Steffen Löck
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany.,Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,German Cancer Consortium (DKTK), Partner Site Dresden, and German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Antje-Christin Knopf
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.,Department 1 of Internal Medicine, Center for Integrated Oncology Cologne, University Hospital of Cologne, Cologne, Germany
| | - Esther G C Troost
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany.,Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Dresden, Germany.,Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,German Cancer Consortium (DKTK), Partner Site Dresden, and German Cancer Research Center (DKFZ), Heidelberg, Germany.,National Center for Tumor Diseases (NCT), Partner Site Dresden, Germany: German Cancer Research Center (DKFZ), Heidelberg, Germany, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany, and; Helmholtz Association / Helmholtz-Zentrum Dresden - Rossendorf (HZDR), Dresden, Germany
| | - Christian Richter
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany.,Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Dresden, Germany.,Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,German Cancer Consortium (DKTK), Partner Site Dresden, and German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Kristin Stützer
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany.,Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Dresden, Germany
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14
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Pakela JM, Knopf A, Dong L, Rucinski A, Zou W. Management of Motion and Anatomical Variations in Charged Particle Therapy: Past, Present, and Into the Future. Front Oncol 2022; 12:806153. [PMID: 35356213 PMCID: PMC8959592 DOI: 10.3389/fonc.2022.806153] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 02/04/2022] [Indexed: 12/14/2022] Open
Abstract
The major aim of radiation therapy is to provide curative or palliative treatment to cancerous malignancies while minimizing damage to healthy tissues. Charged particle radiotherapy utilizing carbon ions or protons is uniquely suited for this task due to its ability to achieve highly conformal dose distributions around the tumor volume. For these treatment modalities, uncertainties in the localization of patient anatomy due to inter- and intra-fractional motion present a heightened risk of undesired dose delivery. A diverse range of mitigation strategies have been developed and clinically implemented in various disease sites to monitor and correct for patient motion, but much work remains. This review provides an overview of current clinical practices for inter and intra-fractional motion management in charged particle therapy, including motion control, current imaging and motion tracking modalities, as well as treatment planning and delivery techniques. We also cover progress to date on emerging technologies including particle-based radiography imaging, novel treatment delivery methods such as tumor tracking and FLASH, and artificial intelligence and discuss their potential impact towards improving or increasing the challenge of motion mitigation in charged particle therapy.
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Affiliation(s)
- Julia M. Pakela
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, United States
| | - Antje Knopf
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
- Department I of Internal Medicine, Center for Integrated Oncology Cologne, University Hospital of Cologne, Cologne, Germany
| | - Lei Dong
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, United States
| | - Antoni Rucinski
- Institute of Nuclear Physics, Polish Academy of Sciences, Krakow, Poland
| | - Wei Zou
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, United States
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15
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Knopf AC, Czerska K, Fracchiolla F, Graeff C, Molinelli S, Rinaldi I, Rucincki A, Sterpin E, Stützer K, Trnkova P, Zhang Y, Chang JY, Giap H, Liu W, Schild SE, Simone CB, Lomax AJ, Meijers A. Clinical necessity of multi-image based (4DMIB) optimization for targets affected by respiratory motion and treated with scanned particle therapy – a comprehensive review. Radiother Oncol 2022; 169:77-85. [DOI: 10.1016/j.radonc.2022.02.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 01/31/2022] [Accepted: 02/14/2022] [Indexed: 12/28/2022]
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16
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Tambas M, van der Laan HP, Steenbakkers RJHM, Doyen J, Timmermann B, Orlandi E, Hoyer M, Haustermans K, Georg P, Burnet NG, Gregoire V, Calugaru V, Troost EGC, Hoebers F, Calvo FA, Widder J, Eberle F, van Vulpen M, Maingon P, Skóra T, Weber DC, Bergfeldt K, Kubes J, Langendijk JA. Current practice in proton therapy delivery in adult cancer patients across Europe. Radiother Oncol 2021; 167:7-13. [PMID: 34902370 DOI: 10.1016/j.radonc.2021.12.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 11/18/2021] [Accepted: 12/05/2021] [Indexed: 12/22/2022]
Abstract
BACKGROUND AND PURPOSE Major differences exist among proton therapy (PT) centres regarding PT delivery in adult cancer patient. To obtain insight into current practice in Europe, we performed a survey among European PT centres. MATERIALS AND METHODS We designed electronic questionnaires for eight tumour sites, focusing on four main topics: 1) indications and patient selection methods; 2) reimbursement; 3) on-going or planned studies, 4) annual number of patients treated with PT. RESULTS Of 22 centres, 19 (86%) responded. In total, 4233 adult patients are currently treated across Europe annually, of which 46% consists of patients with central nervous system tumours (CNS), 15% head and neck cancer (HNC), 15% prostate, 9% breast, 5% lung, 5% gastrointestinal, 4% lymphoma, 0.3% gynaecological cancers. CNS are treated in all participating centres (n = 19) using PT, HNC in 16 centres, lymphoma in 10 centres, gastrointestinal in 10 centres, breast in 7 centres, prostate in 6 centres, lung in 6 centres, and gynaecological cancers in 3 centres. Reimbursement is provided by national health care systems for the majority of commonly treated tumour sites. Approximately 74% of centres enrol patients for prospective data registration programs. Phase II-III trials are less frequent, due to reimbursement and funding problems. Reasons for not treating certain tumour types with PT are lack of evidence (30%), reimbursement issues (29%) and/or technical limitations (20%). CONCLUSION Across European PT centres, CNS tumours and HNC are the most frequently treated tumour types. Most centres use indication protocols. Lack of evidence for PT and reimbursement issues are the most reported reasons for not treating specific tumour types with PT.
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Affiliation(s)
- Makbule Tambas
- University of Groningen, University Medical Center Groningen, Department of Radiation Oncology, The Netherlands.
| | - Hans Paul van der Laan
- University of Groningen, University Medical Center Groningen, Department of Radiation Oncology, The Netherlands
| | - Roel J H M Steenbakkers
- University of Groningen, University Medical Center Groningen, Department of Radiation Oncology, The Netherlands
| | - Jerome Doyen
- Department of Radiation Oncology, Centre Antoine-Lacassagne, University of Côte d'Azur, Nice, France
| | - Beate Timmermann
- Department of Particle Therapy, University Hospital Essen, West German Proton Therapy Centre Essen (WPE), West German Cancer Center (WTZ), Germany; German Cancer Consortium (DKTK), Germany
| | - Ester Orlandi
- Radiation Oncology Clinical Department, National Center for Oncological Hadrontherapy (CNAO), Pavia, Italy
| | - Morten Hoyer
- Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark
| | | | | | - Neil G Burnet
- Proton Beam Therapy Centre, The Christie NHS Foundation Trust, Manchester, UK
| | | | - Valentin Calugaru
- Institut Curie, Radiation Oncology Department, Paris & Proton Center, Orsay, France
| | - Esther G C Troost
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Germany; Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany; Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Dresden, Germany; National Center for Tumor Diseases (NCT), Partner Site Dresden, Germany: German Cancer Research Center (DKFZ), Heidelberg, Germany; Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany; Helmholtz Association / Helmholtz-Zentrum Dresden - Rossendorf (HZDR), Germany; German Cancer Consortium (DKTK), Partner Site Dresden, and German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Frank Hoebers
- Department of Radiation Oncology (MAASTRO Clinic), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre+, The Netherlands
| | - Felipe A Calvo
- Department of Radiation Oncology, University of Navarra, Madrid, Spain
| | - Joachim Widder
- Department of Radiation Oncology, Comprehensive Cancer Center Vienna, Medical University of Vienna, Austria
| | - Fabian Eberle
- Department of Radiotherapy and Radiooncology, University Hospital Marburg, Marburg Ion-Beam Therapy Center (MIT), University Center for Tumor Diseases Frankfurt and Marburg (UCT), Germany
| | | | - Philippe Maingon
- Sorbonne University, AP-HP. Sorbonne University, Hôpitaux Universitaires La Pitié Salpêtrière, Paris, France
| | - Tomasz Skóra
- Maria Skłodowska-Curie National Research Institute of Oncology, Department of Radiotherapy, Kraków, Poland
| | - Damien C Weber
- Center for Proton Therapy, Paul Scherrer Institute, ETH Domain, Switzerland
| | | | - Jiri Kubes
- Depatment of Oncology, Motol University Hospital and Proton Therapy Center Czech, Prague, Czech Republic
| | - Johannes A Langendijk
- University of Groningen, University Medical Center Groningen, Department of Radiation Oncology, The Netherlands
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17
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Chuong MD, Hallemeier CL, Li H, Zhu XR, Zhang X, Tryggestad EJ, Yu J, Yang M, Choi JI, Kang M, Liu W, Knopf A, Meijers A, Molitoris JK, Apisarnthanarax S, Giap H, Hoppe BS, Lee P, Chang JY, Simone CB, Lin SH. Executive Summary of Clinical and Technical Guidelines for Esophageal Cancer Proton Beam Therapy From the Particle Therapy Co-Operative Group Thoracic and Gastrointestinal Subcommittees. Front Oncol 2021; 11:748331. [PMID: 34737959 PMCID: PMC8560961 DOI: 10.3389/fonc.2021.748331] [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: 07/27/2021] [Accepted: 09/28/2021] [Indexed: 02/02/2023] Open
Abstract
Radiation therapy (RT) is an integral component of potentially curative management of esophageal cancer (EC). However, RT can cause significant acute and late morbidity due to excess radiation exposure to nearby critical organs, especially the heart and lungs. Sparing these organs from both low and high radiation dose has been demonstrated to achieve clinically meaningful reductions in toxicity and may improve long-term survival. Accruing dosimetry and clinical evidence support the consideration of proton beam therapy (PBT) for the management of EC. There are critical treatment planning and delivery uncertainties that should be considered when treating EC with PBT, especially as there may be substantial motion-related interplay effects. The Particle Therapy Co-operative Group Thoracic and Gastrointestinal Subcommittees jointly developed guidelines regarding patient selection, treatment planning, clinical trials, and future directions of PBT for EC.
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Affiliation(s)
- Michael D Chuong
- Department of Radiation Oncology, Miami Cancer Institute, Miami, FL, United States
| | | | - Heng Li
- Department of Radiation Oncology, Johns Hopkins University, Baltimore, MD, United States
| | - Xiaorong Ronald Zhu
- Department of Radiation Oncology, MD Anderson Cancer Center, Houston, TX, United States
| | - Xiaodong Zhang
- Department of Radiation Oncology, MD Anderson Cancer Center, Houston, TX, United States
| | - Erik J Tryggestad
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN, United States
| | - Jen Yu
- Department of Radiation Oncology, Miami Cancer Institute, Miami, FL, United States
| | - Ming Yang
- Department of Radiation Oncology, MD Anderson Cancer Center, Houston, TX, United States
| | - J Isabelle Choi
- Department of Radiation Oncology, New York Proton Center, New York, NY, United States
| | - Minglei Kang
- Department of Radiation Oncology, New York Proton Center, New York, NY, United States
| | - Wei Liu
- Department of Radiation Oncology, Mayo Clinic, Scottsdale, AZ, United States
| | - Antje Knopf
- Department of Radiation Oncology, University of Groningen, Groningen, Netherlands
| | - Arturs Meijers
- Department of Radiation Oncology, University of Groningen, Groningen, Netherlands
| | - Jason K Molitoris
- Department of Radiation Oncology, University of Maryland, Baltimore, Baltimore, MD, United States
| | - Smith Apisarnthanarax
- Department of Radiation Oncology, University of Washington, Seattle, WA, United States
| | - Huan Giap
- Department of Radiation Oncology, University of Miami, Miami, FL, United States
| | - Bradford S Hoppe
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL, United States
| | - Percy Lee
- Department of Radiation Oncology, MD Anderson Cancer Center, Houston, TX, United States
| | - Joe Y Chang
- Department of Radiation Oncology, MD Anderson Cancer Center, Houston, TX, United States
| | - Charles B Simone
- Department of Radiation Oncology, New York Proton Center, New York, NY, United States
| | - Steven H Lin
- Department of Radiation Oncology, MD Anderson Cancer Center, Houston, TX, United States
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18
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Aznar M, Ntentas G, Enmark M, Flampouri S, Meidhal Petersen P, Ricardi U, Levis M. The role of motion management and position verification in lymphoma radiotherapy. Br J Radiol 2021; 94:20210618. [PMID: 34677090 PMCID: PMC8553184 DOI: 10.1259/bjr.20210618] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 09/09/2021] [Accepted: 09/10/2021] [Indexed: 12/17/2022] Open
Abstract
In the last decades, the substantial technical progress in radiation oncology offered the opportunity for more accurate planning and delivery of treatment. At the same time, the evolution of systemic treatment and the advent of modern diagnostic tools allowed for more accurate staging and consequently a safe reduction of radiotherapy (RT) target volumes and RT doses in the treatment of lymphomas. As a result, incidental irradiation of organs at risk was reduced, with a consequent reduction of severe late toxicity in long-term lymphoma survivors. Nevertheless, these innovations warrant that professionals pay attention to concurrently ensure precise planning and dose delivery to the target volume and safe sparing of the organs at risk. In particular, target and organ motion should be carefully managed in order to prevent any compromise of treatment efficacy. Several aspects should be taken into account during the treatment pathway to minimise uncertainties and to apply a valuable motion management strategy, when needed. These include: reliable image registration between diagnostic and planning radiologic exams to facilitate the contouring process, image guidance to limit positioning uncertainties and to ensure the accuracy of dose delivery and management of lung motion through procedures of respiratory gating and breath control. In this review, we will cover the current clinical approaches to minimise these uncertainties in patients treated with modern RT techniques, with a particular focus on mediastinal lymphoma. In addition, since uncertainties have a different impact on the dose deposition of protons compared to conventional x-rays, the role of motion management and position verification in proton beam therapy (PBT) will be discussed in a separate section.
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Affiliation(s)
| | | | | | - Stella Flampouri
- Department of Radiation Oncology, Emory University, Atlanta, GA, USA
| | | | | | - Mario Levis
- Department of Oncology, University of Torino, Turin, Italy
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19
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Visser S, den Otter LA, Ribeiro CO, Korevaar EW, Both S, Langendijk JA, Muijs CT, Sijtsema NM, Knopf A. Diaphragm-Based Position Verification to Improve Daily Target Dose Coverage in Proton and Photon Radiation Therapy Treatment of Distal Esophageal Cancer. Int J Radiat Oncol Biol Phys 2021; 112:463-474. [PMID: 34530091 DOI: 10.1016/j.ijrobp.2021.09.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 08/21/2021] [Accepted: 09/06/2021] [Indexed: 12/23/2022]
Abstract
PURPOSE In modern conformal radiation therapy of distal esophageal cancer, target coverage can be affected by variations in the diaphragm position. We investigated if daily position verification (PV) extended by a diaphragm position correction would optimize target dose coverage for esophageal cancer treatment. METHODS AND MATERIALS For 15 esophageal cancer patients, intensity modulated proton therapy (IMPT) and volumetric modulated arc therapy (VMAT) plans were computed. Displacements of the target volume were correlated with diaphragm displacements using repeated 4-dimensional computed tomography images to determine the correction needed to account for diaphragm variations. Afterwards, target coverage was evaluated for 3 PV approaches based on: (1) bony anatomy (PV_B), (2) bony anatomy corrected for the diaphragm position (PV_BD) and (3) target volume (PV_T). RESULTS The cranial-caudal mean target displacement was congruent with almost half of the diaphragm displacement (y = 0.459x), which was used for the diaphragm correction in PV_BD. Target dose coverage using PV_B was adequate for most patients with diaphragm displacements up till 10 mm (≥94% of the dose in 98% of the volume [D98%]). For larger displacements, the target coverage was better maintained by PV_T and PV_BD. Overall, PV_BD accounted best for target displacements, especially in combination with tissue density variations (D98%: IMPT 94% ± 5%, VMAT 96% ± 5%). Diaphragm displacements of more than 10 mm were observed in 22% of the cases. CONCLUSIONS PV_B was sufficient to achieve adequate target dose coverage in case of small deviations in diaphragm position. However, large deviations of the diaphragm were best mitigated by PV_BD. To detect the cases where target dose coverage could be compromised due to diaphragm position variations, we recommend monitoring of the diaphragm position before treatment through online imaging.
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Affiliation(s)
- Sabine Visser
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
| | - Lydia A den Otter
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Cássia O Ribeiro
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Erik W Korevaar
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Stefan Both
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Johannes A Langendijk
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Christina T Muijs
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Nanna M Sijtsema
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Antje Knopf
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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20
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Visser S, Neh H, Oraboni Ribeiro C, Korevaar EW, Meijers A, Poppe B, Sijtsema NM, Both S, Langendijk JA, Muijs CT, Knopf AC. Assessment of a diaphragm override strategy for robustly optimized proton therapy planning for esophageal cancer patients. Med Phys 2021; 48:5674-5683. [PMID: 34289123 PMCID: PMC9291176 DOI: 10.1002/mp.15114] [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: 06/24/2020] [Revised: 01/03/2021] [Accepted: 06/23/2021] [Indexed: 12/25/2022] Open
Abstract
Purpose To ensure target coverage in the treatment of esophageal cancer, a density override to the region of diaphragm motion can be applied in the optimization process. Here, we evaluate the benefit of this approach during robust optimization for intensity modulated proton therapy (IMPT) planning. Materials and methods For 10 esophageal cancer patients, two robustly optimized IMPT plans were created either using (WDO) or not using (NDO) a diaphragm density override of 1.05 g/cm3 during plan optimization. The override was applied to the excursion of the diaphragm between exhale and inhale. Initial robustness evaluation was performed for plan acceptance (setup errors of 8 mm, range errors of ±3%), and subsequently, on all weekly repeated 4DCTs (setup errors of 2 mm, range errors of ±3%). Target coverage and hotspots were analyzed on the resulting voxel‐wise minimum (Vwmin) and voxel‐wise maximum (Vwmax) dose distributions. Results The nominal dose distributions were similar for both WDO and NDO plans. However, visual inspection of the Vwmax of the WDO plans showed hotspots behind the right diaphragm override region. For one patient, target coverage and hotspots improved by applying the diaphragm override. We found no differences in target coverage in the weekly evaluations between the two approaches. Conclusion The diaphragm override approach did not result in a clinical benefit in terms of planning and interfractional robustness. Therefore, we do not see added value in employing this approach as a default option during robust optimization for IMPT planning in esophageal cancer.
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Affiliation(s)
- Sabine Visser
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Hendrike Neh
- Division for Medical Radiation Physics, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Cássia Oraboni Ribeiro
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Erik W Korevaar
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Arturs Meijers
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Björn Poppe
- Division for Medical Radiation Physics, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Nanna M Sijtsema
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Stefan Both
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Johannes A Langendijk
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Christina T Muijs
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Antje C Knopf
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.,Division for Medical Radiation Physics, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
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21
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Taasti VT, Hattu D, Vaassen F, Canters R, Velders M, Mannens J, van Loon J, Rinaldi I, Unipan M, van Elmpt W. Treatment planning and 4D robust evaluation strategy for proton therapy of lung tumors with large motion amplitude. Med Phys 2021; 48:4425-4437. [PMID: 34214201 PMCID: PMC8456954 DOI: 10.1002/mp.15067] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 05/29/2021] [Accepted: 06/21/2021] [Indexed: 12/25/2022] Open
Abstract
Purpose Intensity‐modulated proton therapy (IMPT) for lung tumors with a large tumor movement is challenging due to loss of robustness in the target coverage. Often an upper cut‐off at 5‐mm tumor movement is used for proton patient selection. In this study, we propose (1) a robust and easily implementable treatment planning strategy for lung tumors with a movement larger than 5 mm, and (2) a four‐dimensional computed tomography (4DCT) robust evaluation strategy for evaluating the dose distribution on the breathing phases. Materials and methods We created a treatment planning strategy based on the internal target volume (ITV) concept (aim 1). The ITV was created as a union of the clinical target volumes (CTVs) on the eight 4DCT phases. The ITV expanded by 2 mm was the target during robust optimization on the average CT (avgCT). The clinical plan acceptability was judged based on a robust evaluation, computing the voxel‐wise min and max (VWmin/max) doses over 28 error scenarios (range and setup errors) on the avgCT. The plans were created in RayStation (RaySearch Laboratories, Stockholm, Sweden) using a Monte Carlo dose engine, commissioned for our Mevion S250i Hyperscan system (Mevion Medical Systems, Littleton, MA, USA). We developed a new 4D robust evaluation approach (4DRobAvg; aim 2). The 28 scenario doses were computed on each individual 4DCT phase. For each scenario, the dose distributions on the individual phases were deformed to the reference phase and combined to a weighted sum, resulting in 28 weighted sum scenario dose distributions. From these 28 scenario doses, VWmin/max doses were computed. This new 4D robust evaluation was compared to two simpler 4D evaluation strategies: re‐computing the nominal plan on each individual 4DCT phase (4DNom) and computing the robust VWmin/max doses on each individual phase (4DRobInd). The treatment planning and dose evaluation strategies were evaluated for 16 lung cancer patients with tumor movement of 4–26 mm. Results The ratio of the ITV and CTV volumes increased linearly with the tumor amplitude, with an average ratio of 1.4. Despite large ITV volumes, a clinically acceptable plan fulfilling all target and organ at risk (OAR) constraints was feasible for all patients. The 4DNom and 4DRobInd evaluation strategies were found to under‐ or overestimate the dosimetric effect of the tumor movement, respectively. 4DRobInd showed target underdosage for five patients, not observed in the robust evaluation on the avgCT or in 4DRobAvg. The accuracy of dose deformation used in 4DRobAvg was quantified and found acceptable, with differences for the dose‐volume parameters below 1 Gy in most cases. Conclusion The proposed ITV‐based planning strategy on the avgCT was found to be a clinically feasible approach with adequate tumor coverage and no OAR overdosage even for large tumor movement. The new proposed 4D robust evaluation, 4DRobAvg, was shown to give an easily interpretable understanding of the effect of respiratory motion dose distribution, and to give an accurate estimate of the dose delivered in the different breathing phases.
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Affiliation(s)
- Vicki Trier Taasti
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology, Maastricht University Medical Centre+, Maastricht, Netherlands
| | - Djoya Hattu
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology, Maastricht University Medical Centre+, Maastricht, Netherlands
| | - Femke Vaassen
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology, Maastricht University Medical Centre+, Maastricht, Netherlands
| | - Richard Canters
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology, Maastricht University Medical Centre+, Maastricht, Netherlands
| | - Marije Velders
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology, Maastricht University Medical Centre+, Maastricht, Netherlands
| | - Jolein Mannens
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology, Maastricht University Medical Centre+, Maastricht, Netherlands
| | - Judith van Loon
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology, Maastricht University Medical Centre+, Maastricht, Netherlands
| | - Ilaria Rinaldi
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology, Maastricht University Medical Centre+, Maastricht, Netherlands
| | - Mirko Unipan
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology, Maastricht University Medical Centre+, Maastricht, Netherlands
| | - Wouter van Elmpt
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology, Maastricht University Medical Centre+, Maastricht, Netherlands
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22
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Møller DS, Poulsen PR, Hagner A, Dufour M, Nordsmark M, Nyeng TB, Mortensen HR, Lutz CM, Hoffmann L. Strategies for Motion Robust Proton Therapy With Pencil Beam Scanning for Esophageal Cancer. Int J Radiat Oncol Biol Phys 2021; 111:539-548. [PMID: 33974885 DOI: 10.1016/j.ijrobp.2021.04.040] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 03/28/2021] [Accepted: 04/26/2021] [Indexed: 10/21/2022]
Abstract
PURPOSE Proton therapy of esophageal cancer is superior to photon radiation therapy in terms of normal tissue sparing. However, respiratory motion and anatomical changes may compromise target dose coverage owing to density changes, geometric misses, and interplay effects. Here we investigate the combined effect on clinical target volume (CTV) coverage and compare proton therapy with intensity modulated radiation therapy (IMRT). METHODS AND MATERIALS This study includes 26 patients with esophageal cancer previously treated with IMRT planned on 4-dimensional computed tomography (4D-CT). For each patient, 7 proton pencil beam scanning (PBS) plans were created with different field configurations and optimization strategies. The effect of respiration was investigated by calculating the phase doses, 4D dose, and 4D dynamic dose (including interplay effects). The effect of anatomical changes was investigated by recalculating all plans on all phases of a 4D-CT surveillance scan. RESULTS The most robust PBS plans were achieved using 2 posterior beams requiring coverage of planning target volume (PTV) and simultaneously using robust optimization (RO) of CTV (2PAPTVRO), resulting in only 1 patient showing V95%CTV <97% in 1 or more phases of the planning CT. For the least robust PBS plans obtained using lateral + posterior beams and CTV-RO, but not requiring PTV coverage (2LPRO), 10 patients showed underdosage. For IMRT, 2 patients showed underdosage. Interplay effects reduced V95%CTV significantly when delivering only 1 fraction, but the effects generally averaged out after 10 fractions. The effect of interplay was significantly larger for RO-only plans compared with plans optimized with RO combined with PTV coverage. Combining the effect of anatomical changes and respiration on the 4D-CT surveillance scan resulted in V95%CTV <97% for 3 2PAPTVRO, 16 2LPRO, and 8 IMRT patients. CONCLUSIONS PBS using posterior beam angles was more robust to anatomical changes and respiration than IMRT. The effect of respiration was enhanced when anatomical changes were present. Single fraction interplay effects deteriorated the dose distribution but were averaged out after 10 fractions.
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Affiliation(s)
- Ditte Sloth Møller
- Department of Medical Physics, Aarhus University Hospital, Aarhus, Denmark.
| | - Per Rugaard Poulsen
- Department of Oncology, Aarhus University Hospital, Aarhus, Denmark; Danish Center for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark
| | - Andreas Hagner
- Department of Medical Physics, Aarhus University Hospital, Aarhus, Denmark
| | - Mathieu Dufour
- Department of Physics, University of Turin, Turin, Italy
| | | | | | | | | | - Lone Hoffmann
- Department of Medical Physics, Aarhus University Hospital, Aarhus, Denmark
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23
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Botticella A, Levy A, Auzac G, Chabert I, Berthold C, Le Pechoux C. Tumour motion management in lung cancer: a narrative review. Transl Lung Cancer Res 2021; 10:2011-2017. [PMID: 34012810 PMCID: PMC8107759 DOI: 10.21037/tlcr-20-856] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Respiratory motion is one of the geometrical uncertainties that may affect the accuracy of thoracic radiotherapy in the treatment of lung cancer. Accounting for tumour motion may allow reducing treatment volumes, irradiated healthy tissue and possibly toxicity, and finally enabling dose escalation. Historically, large population-based margins were used to encompass tumour motion. A paradigmatic change happened in the last decades led to the development of modern imaging techniques during the simulation and the delivery, such as the 4-dimensional (4D) computed tomography (CT) or the 4D-cone beam CT scan, has contributed to a better understanding of lung tumour motion and to the widespread use of individualised margins (with either an internal tumour volume approach or a mid-position/ventilation approach). Moreover, recent technological advances in the delivery of radiotherapy treatments (with a variety of commercial solution allowing tumour tracking, gating or treatments in deep-inspiration breath-hold) conjugate the necessity of minimising treatment volumes while maximizing the patient comfort with less invasive techniques. In this narrative review, we provided an introduction on the intra-fraction tumour motion (in both lung tumours and mediastinal lymph-nodes), and summarized the principal motion management strategies (in both the imaging and the treatment delivery) in thoracic radiotherapy for lung cancer, with an eye on the clinical outcomes.
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Affiliation(s)
- Angela Botticella
- Department of Radiation Oncology, Institut d'Oncologie Thoracique (IOT), Gustave Roussy, F-94805, Villejuif, France
| | - Antonin Levy
- Department of Radiation Oncology, Institut d'Oncologie Thoracique (IOT), Gustave Roussy, F-94805, Villejuif, France.,Univ Paris Sud, Université Paris-Saclay, F-94270, Le Kremlin-Bicêtre, France.,INSERM U1030, Molecular Radiotherapy, Gustave Roussy, Université Paris-Saclay, F-94805, Villejuif, France
| | - Guillaume Auzac
- Department of Radiation Oncology, Institut d'Oncologie Thoracique (IOT), Gustave Roussy, F-94805, Villejuif, France
| | - Isabelle Chabert
- Department of Radiation Oncology, Institut d'Oncologie Thoracique (IOT), Gustave Roussy, F-94805, Villejuif, France
| | - Céline Berthold
- Department of Radiation Oncology, Institut d'Oncologie Thoracique (IOT), Gustave Roussy, F-94805, Villejuif, France
| | - Cécile Le Pechoux
- Department of Radiation Oncology, Institut d'Oncologie Thoracique (IOT), Gustave Roussy, F-94805, Villejuif, France
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24
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Ribeiro CO, Visser S, Korevaar EW, Sijtsema NM, Anakotta RM, Dieters M, Both S, Langendijk JA, Wijsman R, Muijs CT, Meijers A, Knopf A. Towards the clinical implementation of intensity-modulated proton therapy for thoracic indications with moderate motion: Robust optimised plan evaluation by means of patient and machine specific information. Radiother Oncol 2021; 157:210-218. [DOI: 10.1016/j.radonc.2021.01.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 12/09/2020] [Accepted: 01/06/2021] [Indexed: 02/09/2023]
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25
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Nenoff L, Matter M, Amaya EJ, Josipovic M, Knopf AC, Lomax AJ, Persson GF, Ribeiro CO, Visser S, Walser M, Weber DC, Zhang Y, Albertini F. Dosimetric influence of deformable image registration uncertainties on propagated structures for online daily adaptive proton therapy of lung cancer patients. Radiother Oncol 2021; 159:136-143. [PMID: 33771576 DOI: 10.1016/j.radonc.2021.03.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 03/14/2021] [Accepted: 03/15/2021] [Indexed: 12/25/2022]
Abstract
PURPOSE A major burden of introducing an online daily adaptive proton therapy (DAPT) workflow is the time and resources needed to correct the daily propagated contours. In this study, we evaluated the dosimetric impact of neglecting the online correction of the propagated contours in a DAPT workflow. MATERIAL AND METHODS For five NSCLC patients with nine repeated deep-inspiration breath-hold CTs, proton therapy plans were optimised on the planning CT to deliver 60 Gy-RBE in 30 fractions. All repeated CTs were registered with six different clinically used deformable image registration (DIR) algorithms to the corresponding planning CT. Structures were propagated rigidly and with each DIR algorithm and reference structures were contoured on each repeated CT. DAPT plans were optimised with the uncorrected, propagated structures (propagated DAPT doses) and on the reference structures (ideal DAPT doses), non-adapted doses were recalculated on all repeated CTs. RESULTS Due to anatomical changes occurring during the therapy, the clinical target volume (CTV) coverage of the non-adapted doses reduces on average by 9.7% (V95) compared to an ideal DAPT doses. For the propagated DAPT doses, the CTV coverage was always restored (average differences in the CTV V95 < 1% compared to the ideal DAPT doses). Hotspots were always reduced with any DAPT approach. CONCLUSION For the patients presented here, a benefit of online DAPT was shown, even if the daily optimisation is based on propagated structures with some residual uncertainties. However, a careful (offline) structure review is necessary and corrections can be included in an offline adaption.
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Affiliation(s)
- Lena Nenoff
- Paul Scherrer Institute, Center for Proton Therapy, Switzerland; Department of Physics, ETH Zurich, Switzerland.
| | - Michael Matter
- Paul Scherrer Institute, Center for Proton Therapy, Switzerland; Department of Physics, ETH Zurich, Switzerland
| | | | - Mirjana Josipovic
- Department of Oncology, Rigshospitalet Copenhagen University Hospital, Denmark
| | - Antje-Christin Knopf
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands
| | - Antony John Lomax
- Paul Scherrer Institute, Center for Proton Therapy, Switzerland; Department of Physics, ETH Zurich, Switzerland
| | - Gitte F Persson
- Department of Oncology, Rigshospitalet Copenhagen University Hospital, Denmark; Department of Oncology, Herlev-Gentofte Hospital Copenhagen University Hospital, Denmark; Department of Clinical Medicine, Faculty of Medical Sciences, University of Copenhagen, Denmark
| | - Cássia O Ribeiro
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands
| | - Sabine Visser
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands
| | - Marc Walser
- Paul Scherrer Institute, Center for Proton Therapy, Switzerland
| | - Damien Charles Weber
- Paul Scherrer Institute, Center for Proton Therapy, Switzerland; Department of Radiation Oncology, University Hospital Zurich, Switzerland; Department of Radiation Oncology, University Hospital Bern, Switzerland
| | - Ye Zhang
- Paul Scherrer Institute, Center for Proton Therapy, Switzerland
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26
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Paganetti H, Beltran C, Both S, Dong L, Flanz J, Furutani K, Grassberger C, Grosshans DR, Knopf AC, Langendijk JA, Nystrom H, Parodi K, Raaymakers BW, Richter C, Sawakuchi GO, Schippers M, Shaitelman SF, Teo BKK, Unkelbach J, Wohlfahrt P, Lomax T. Roadmap: proton therapy physics and biology. Phys Med Biol 2021; 66. [DOI: 10.1088/1361-6560/abcd16] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 11/23/2020] [Indexed: 12/12/2022]
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Czerska K, Emert F, Kopec R, Langen K, McClelland JR, Meijers A, Miyamoto N, Riboldi M, Shimizu S, Terunuma T, Zou W, Knopf A, Rucinski A. Clinical practice vs. state-of-the-art research and future visions: Report on the 4D treatment planning workshop for particle therapy - Edition 2018 and 2019. Phys Med 2021; 82:54-63. [PMID: 33588228 DOI: 10.1016/j.ejmp.2020.12.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 12/09/2020] [Accepted: 12/16/2020] [Indexed: 12/18/2022] Open
Abstract
The 4D Treatment Planning Workshop for Particle Therapy, a workshop dedicated to the treatment of moving targets with scanned particle beams, started in 2009 and since then has been organized annually. The mission of the workshop is to create an informal ground for clinical medical physicists, medical physics researchers and medical doctors interested in the development of the 4D technology, protocols and their translation into clinical practice. The 10th and 11th editions of the workshop took place in Sapporo, Japan in 2018 and Krakow, Poland in 2019, respectively. This review report from the Sapporo and Krakow workshops is structured in two parts, according to the workshop programs. The first part comprises clinicians and physicists review of the status of 4D clinical implementations. Corresponding talks were given by speakers from five centers around the world: Maastro Clinic (The Netherlands), University Medical Center Groningen (The Netherlands), MD Anderson Cancer Center (United States), University of Pennsylvania (United States) and The Proton Beam Therapy Center of Hokkaido University Hospital (Japan). The second part is dedicated to novelties in 4D research, i.e. motion modelling, artificial intelligence and new technologies which are currently being investigated in the radiotherapy field.
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Affiliation(s)
- Katarzyna Czerska
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342 Krakow, Poland.
| | - Frank Emert
- Center for Proton Therapy, Paul Scherrer Institute, Switzerland
| | - Renata Kopec
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342 Krakow, Poland
| | - Katja Langen
- Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA, USA
| | - Jamie R McClelland
- Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Arturs Meijers
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Naoki Miyamoto
- Department of Medical Physics, Hokkaido University Hospital, Sapporo, Hokkaido, Japan; Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Marco Riboldi
- Department of Medical Physics, Ludwig-Maximilians-Universität München, Germany
| | - Shinichi Shimizu
- Department of Medical Physics, Hokkaido University Hospital, Sapporo, Hokkaido, Japan; Department of Radiation Medical Science and Engineering, Faculty of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Toshiyuki Terunuma
- Faculty of Medicine, University of Tsukuba, Japan; Proton Medical Research Center, University of Tsukuba Hospital, Japan
| | - Wei Zou
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA
| | - Antje Knopf
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Antoni Rucinski
- Institute of Nuclear Physics Polish Academy of Sciences, PL-31342 Krakow, Poland
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Ribeiro CO, Terpstra J, Janssens G, Langendijk JA, Both S, Muijs CT, Wijsman R, Knopf A, Meijers A. Evaluation of continuous beam rescanning versus pulsed beam in pencil beam scanned proton therapy for lung tumours. Phys Med Biol 2020; 65:23NT01. [PMID: 33120367 DOI: 10.1088/1361-6560/abc5c8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The treatment of moving targets with pencil beam scanned proton therapy (PBS-PT) may rely on rescanning strategies to smooth out motion induced dosimetric disturbances. PBS-PT machines, such as Proteus®Plus (PPlus) and Proteus®One (POne), deliver a continuous or a pulsed beam, respectively. In PPlus, scaled (or no) rescanning can be applied, while POne implies intrinsic 'rescanning' due to its pulsed delivery. We investigated the efficacy of these PBS-PT delivery types for the treatment of lung tumours. In general, clinically acceptable plans were achieved, and PPlus and POne showed similar effectiveness.
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Affiliation(s)
- Cássia O Ribeiro
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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Mitigation of motion effects in pencil-beam scanning - Impact of repainting on 4D robustly optimized proton treatment plans for hepatocellular carcinoma. Z Med Phys 2020; 32:63-73. [PMID: 33131995 PMCID: PMC9948857 DOI: 10.1016/j.zemedi.2020.08.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 07/29/2020] [Accepted: 08/14/2020] [Indexed: 12/27/2022]
Abstract
Proton fields delivered by the active scanning technique can be interfered with the intrafractional motion. This in-silico study seeks to mitigate the dosimetric impacts of motion artifacts, especially its interplay with the time-modulated dose delivery. Here four-dimensional (4d) robust optimization and dose repainting, which is the multiple application of the same field with reduced fluence, were combined. Two types of repainting were considered: layered and volumetric repainting. The time-resolved dose calculation, which is necessary to quantify the interplay effect, was integrated into the treatment planning system and validated. Nine clinical cases of hepatocellular carcinoma (HCC) showing motion in the range of 0.4-1.5cm were studied. It was found that the repainted delivery of 4D robustly optimized plans reduced the impact of interplay effect as quantified by the homogeneity index within the clinical target volume (CTV) to a tolerable level. Similarly, the fractional over- and underdosage was reduced sufficiently for some HCC cases to achieve the purpose of motion management. This holds true for both investigated types of repainting with small dosimetric advantages of volume repainting over layered repainting. Volume repainting, however, cannot be applied clinically in proton centers with slow energy changes. Thus, it served as a reference in the in-silico evaluation. It is recommended to perform the dynamic dose calculation for individual cases to judge if robust optimization in conjunction with repainting is sufficient to keep the interplay effect within bounds.
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30
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Shan J, Yang Y, Schild SE, Daniels TB, Wong WW, Fatyga M, Bues M, Sio TT, Liu W. Intensity-modulated proton therapy (IMPT) interplay effect evaluation of asymmetric breathing with simultaneous uncertainty considerations in patients with non-small cell lung cancer. Med Phys 2020; 47:5428-5440. [PMID: 32964474 DOI: 10.1002/mp.14491] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 07/14/2020] [Accepted: 09/11/2020] [Indexed: 12/15/2022] Open
Abstract
PURPOSE Intensity-modulated proton therapy (IMPT) is sensitive to uncertainties from patient setup and proton beam range, as well as interplay effect. In addition, respiratory motion may vary from cycle to cycle, and also from day to day. These uncertainties can severely degrade the original plan quality and potentially affect patient's outcome. In this work, we developed a new tool to comprehensively consider the impact of all these uncertainties and provide plan robustness evaluation under them. METHODS We developed a comprehensive plan robustness evaluation tool that considered both uncertainties from patient setup and proton beam range, as well as respiratory motion simultaneously. To mimic patients' respiratory motion, the time spent in each phase was randomly sampled based on patient-specific breathing pattern parameters as acquired during the four-dimensional (4D)-computed tomography (CT) simulation. Spots were then assigned to one specific phase according to the temporal relationship between spot delivery sequence and patients' respiratory motion. Dose in each phase was calculated by summing contributions from all the spots delivered in that phase. The final 4D dynamic dose was obtained by deforming all doses in each phase to the maximum exhalation phase. Three hundred (300) scenarios (10 different breathing patterns with 30 different setup and range uncertainty scenario combinations) were calculated for each plan. The dose-volume histograms (DVHs) band method was used to assess plan robustness. Benchmarking the tool as an application's example, we compared plan robustness under both three-dimensional (3D) and 4D robustly optimized IMPT plans for 10 nonrandomly selected patients with non-small cell lung cancer. RESULTS The developed comprehensive plan robustness tool had been successfully applied to compare the plan robustness between 3D and 4D robustly optimized IMPT plans for 10 lung cancer patients. In the presence of interplay effect with uncertainties considered simultaneously, 4D robustly optimized plans provided significantly better CTV coverage (D95% , P = 0.002), CTV homogeneity (D5% -D95% , P = 0.002) with less target hot spots (D5% , P = 0.002), and target coverage robustness (CTV D95% bandwidth, P = 0.004) compared to 3D robustly optimized plans. Superior dose sparing of normal lung (lung Dmean , P = 0.020) favoring 4D plans and comparable normal tissue sparing including esophagus, heart, and spinal cord for both 3D and 4D plans were observed. The calculation time for all patients included in this study was 11.4 ± 2.6 min. CONCLUSION A comprehensive plan robustness evaluation tool was successfully developed and benchmarked for plan robustness evaluation in the presence of interplay effect, setup and range uncertainties. The very high efficiency of this tool marks its clinical adaptation, highly practical and versatile nature, including possible real-time intra-fractional interplay effect evaluation as a potential application for future use.
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Affiliation(s)
- Jie Shan
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - Yunze Yang
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - Steven E Schild
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - Thomas B Daniels
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - William W Wong
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - Mirek Fatyga
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - Martin Bues
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - Terence T Sio
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - Wei Liu
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
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31
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Gort EM, Beukema JC, Matysiak W, Sijtsema NM, Aluwini S, Langendijk JA, Both S, Brouwer CL. Inter-fraction motion robustness and organ sparing potential of proton therapy for cervical cancer. Radiother Oncol 2020; 154:194-200. [PMID: 32956707 DOI: 10.1016/j.radonc.2020.09.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 08/05/2020] [Accepted: 09/02/2020] [Indexed: 11/19/2022]
Abstract
PURPOSE Large-field photon radiotherapy is current standard in the treatment of cervical cancer patients. However, with the increasing availability of Pencil Beam Scanning Proton Therapy (PBS-PT) and robust treatment planning techniques, protons may have significant advantages for cervical cancer patients in the reduction of toxicity. In this study, PBS-PT and photon Volumetric Modulated Arc Therapy (VMAT) were compared, examining target coverage and organ at risk (OAR) dose, taking inter- and intra-fraction motion into account. MATERIALS AND METHODS Twelve cervical cancer patients were included in this in-silico planning study. In all cases, a planning CT scan, five weekly repeat CT scans (reCTs) and an additional reCT 10 min after the first reCT were available. Two-arc VMAT and robustly optimised two- and four-field (2F and 4F) PBS-PT plans were robustly evaluated on planCTs and reCTs using set-up and range uncertainty. Nominal OAR doses and voxel-wise minimum target coverage robustness were compared. RESULTS Average voxel-wise minimum accumulated doses for pelvic target structures over all patients were adequate for both photon and proton treatment techniques (D98 > 95%, [91.7-99.3%]). Average accumulated dose of the para-aortic region was lower than the required 95%, D98 > 94.4% [91.1-98.2%]. With PBS-PT 4F, dose to all OARs was significantly lower than with VMAT. Major differences were observed for mean bowel bag V15Gy: 60% [39-70%] for VMAT vs 30% [10-52%] and 32% [9-54%] for PBS-PT 2F and 4F and for mean bone marrow V10Gy: 88% [82-97%] for VMAT vs 66% [60-73%] and 67% [60-75%] for PBS-PT 2F and 4F. CONCLUSION Robustly optimised PBS-PT for cervical cancer patients shows equivalent target robustness against inter- and intra-fraction variability compared to VMAT, and offers significantly better OAR sparing.
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Affiliation(s)
- Elske M Gort
- University of Groningen, University Medical Center Groningen, Department of Radiation Oncology, The Netherlands
| | - Jannet C Beukema
- University of Groningen, University Medical Center Groningen, Department of Radiation Oncology, The Netherlands
| | - Witold Matysiak
- University of Groningen, University Medical Center Groningen, Department of Radiation Oncology, The Netherlands
| | - Nanna M Sijtsema
- University of Groningen, University Medical Center Groningen, Department of Radiation Oncology, The Netherlands
| | - Shafak Aluwini
- University of Groningen, University Medical Center Groningen, Department of Radiation Oncology, The Netherlands
| | - Johannes A Langendijk
- University of Groningen, University Medical Center Groningen, Department of Radiation Oncology, The Netherlands
| | - Stefan Both
- University of Groningen, University Medical Center Groningen, Department of Radiation Oncology, The Netherlands
| | - Charlotte L Brouwer
- University of Groningen, University Medical Center Groningen, Department of Radiation Oncology, The Netherlands.
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32
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Meijers A, Knopf AC, Crijns AP, Ubbels JF, Niezink AG, Langendijk JA, Wijsman R, Both S. Evaluation of interplay and organ motion effects by means of 4D dose reconstruction and accumulation. Radiother Oncol 2020; 150:268-274. [DOI: 10.1016/j.radonc.2020.07.055] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 07/14/2020] [Accepted: 07/23/2020] [Indexed: 12/29/2022]
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33
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den Otter LA, Anakotta RM, Weessies M, Roos CTG, Sijtsema NM, Muijs CT, Dieters M, Wijsman R, Troost EGC, Richter C, Meijers A, Langendijk JA, Both S, Knopf AC. Investigation of inter-fraction target motion variations in the context of pencil beam scanned proton therapy in non-small cell lung cancer patients. Med Phys 2020; 47:3835-3844. [PMID: 32573792 PMCID: PMC7586844 DOI: 10.1002/mp.14345] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 05/01/2020] [Accepted: 06/14/2020] [Indexed: 12/25/2022] Open
Abstract
Purpose For locally advanced‐stage non‐small cell lung cancer (NSCLC), inter‐fraction target motion variations during the whole time span of a fractionated treatment course are assessed in a large and representative patient cohort. The primary objective is to develop a suitable motion monitoring strategy for pencil beam scanning proton therapy (PBS‐PT) treatments of NSCLC patients during free breathing. Methods Weekly 4D computed tomography (4DCT; 41 patients) and daily 4D cone beam computed tomography (4DCBCT; 10 of 41 patients) scans were analyzed for a fully fractionated treatment course. Gross tumor volumes (GTVs) were contoured and the 3D displacement vectors of the centroid positions were compared for all scans. Furthermore, motion amplitude variations in different lung segments were statistically analyzed. The dosimetric impact of target motion variations and target motion assessment was investigated in exemplary patient cases. Results The median observed centroid motion was 3.4 mm (range: 0.2–12.4 mm) with an average variation of 2.2 mm (range: 0.1–8.8 mm). Ten of 32 patients (31.3%) with an initial motion <5 mm increased beyond a 5‐mm motion amplitude during the treatment course. Motion observed in the 4DCBCT scans deviated on average 1.5 mm (range: 0.0–6.0 mm) from the motion observed in the 4DCTs. Larger motion variations for one example patient compromised treatment plan robustness while no dosimetric influence was seen due to motion assessment biases in another example case. Conclusions Target motion variations were investigated during the course of radiotherapy for NSCLC patients. Patients with initial GTV motion amplitudes of < 2 mm can be assumed to be stable in motion during the treatment course. For treatments of NSCLC patients who exhibit motion amplitudes of > 2 mm, 4DCBCT should be considered for motion monitoring due to substantial motion variations observed.
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Affiliation(s)
- Lydia A den Otter
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, 9713 GZ, The Netherlands
| | - Renske M Anakotta
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, 9713 GZ, The Netherlands
| | - Menkedina Weessies
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, 9713 GZ, The Netherlands
| | - Catharina T G Roos
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, 9713 GZ, The Netherlands
| | - Nanna M Sijtsema
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, 9713 GZ, The Netherlands
| | - Christina T Muijs
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, 9713 GZ, The Netherlands
| | - Margriet Dieters
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, 9713 GZ, The Netherlands
| | - Robin Wijsman
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, 9713 GZ, The Netherlands
| | - Esther G C Troost
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden, Rossendorf, Germany.,Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology, OncoRay, Germany.,Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,Partner Site Dresden, and German Cancer Research Center (DKFZ), German Cancer Consortium (DKTK), Heidelberg, Germany.,National Center for Tumor Diseases (NCT), Partner Site Dresden, Dresden, Germany
| | - Christian Richter
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden, Rossendorf, Germany.,Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology, OncoRay, Germany.,Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,Partner Site Dresden, and German Cancer Research Center (DKFZ), German Cancer Consortium (DKTK), Heidelberg, Germany
| | - Arturs Meijers
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, 9713 GZ, The Netherlands
| | - Johannes A Langendijk
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, 9713 GZ, The Netherlands
| | - Stefan Both
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, 9713 GZ, The Netherlands
| | - Antje-Christin Knopf
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, 9713 GZ, The Netherlands
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Zeng J, Badiyan SN, Garces YI, Wong T, Zhang X, Simone CB, Chang JY, Knopf AC, Mori S, Iwata H, Meijers A, Li H, Bues M, Liu W, Schild SE, Rengan R. Consensus Statement on Proton Therapy in Mesothelioma. Pract Radiat Oncol 2020; 11:119-133. [PMID: 32461036 DOI: 10.1016/j.prro.2020.05.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 04/26/2020] [Accepted: 05/13/2020] [Indexed: 12/11/2022]
Abstract
PURPOSE Radiation therapy for mesothelioma remains challenging, as normal tissue toxicity limits the amount of radiation that can be safely delivered to the pleural surfaces, especially radiation dose to the contralateral lung. The physical properties of proton therapy result in better sparing of normal tissues when treating the pleura, both in the postpneumonectomy setting and the lung-intact setting. Compared with photon radiation, there are dramatic reductions in dose to the contralateral lung, heart, liver, kidneys, and stomach. However, the tissue heterogeneity in the thorax, organ motion, and potential for changing anatomy during the treatment course all present challenges to optimal irradiation with protons. METHODS The clinical data underlying proton therapy in mesothelioma are reviewed here, including indications, advantages, and limitations. RESULTS The Particle Therapy Cooperative Group Thoracic Subcommittee task group provides specific guidelines for the use of proton therapy for mesothelioma. CONCLUSIONS This consensus report can be used to guide clinical practice, insurance approval, and future research.
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Affiliation(s)
- Jing Zeng
- Department of Radiation Oncology, University of Washington School of Medicine, Seattle, Washington.
| | - Shahed N Badiyan
- Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri
| | - Yolanda I Garces
- Department of Radiation Oncology, Mayo Clinic Rochester, Rochester, Minnesota
| | - Tony Wong
- Seattle Cancer Care Alliance Proton Therapy Center, Seattle, Washington
| | - Xiaodong Zhang
- Department of Radiation Physics, Division of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas
| | | | - Joe Y Chang
- Department of Radiation Oncology, Division of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Antje C Knopf
- Division of Radiotherapy, University of Groningen, Groningen, Netherlands
| | - Shinichiro Mori
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba, Japan
| | - Hiromitsu Iwata
- Department of Radiation Oncology, Nagoya Proton Therapy Center, Nagoya City West Medical Center, Nagoya, Japan
| | - Arturs Meijers
- Division of Radiotherapy, University of Groningen, Groningen, Netherlands
| | - Heng Li
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins Medicine, Baltimore, Maryland
| | - Martin Bues
- Department of Radiation Oncology, Mayo Clinic Arizona, Scottsdale, Arizona
| | - Wei Liu
- Department of Radiation Oncology, Mayo Clinic Arizona, Scottsdale, Arizona
| | - Steven E Schild
- Department of Radiation Oncology, Mayo Clinic Arizona, Scottsdale, Arizona
| | - Ramesh Rengan
- Department of Radiation Oncology, University of Washington School of Medicine, Seattle, Washington
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van der Laan HP, Anakotta RM, Korevaar EW, Dieters M, Ubbels JF, Wijsman R, Sijtsema NM, Both S, Langendijk JA, Muijs CT, Knopf AC. Organ sparing potential and inter-fraction robustness of adaptive intensity modulated proton therapy for lung cancer. Acta Oncol 2019; 58:1775-1782. [PMID: 31556764 DOI: 10.1080/0284186x.2019.1669818] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Background: The aim of this study was to compare adaptive intensity modulated proton therapy (IMPT) robustness and organ sparing capabilities with that of adaptive volumetric arc photon therapy (VMAT).Material and methods: Eighteen lung cancer patients underwent a planning 4DCT (p4DCT) and 5 weekly repeated 4DCT (r4DCT) scans. Target volumes and organs at risk were manually delineated on the three-dimensional (3D) average scans of the p4DCT (av_p4DCT) and of the r4DCT scans (av_r4DCT). Planning target volume (PTV)-based VMAT plans and internal clinical target volume (ICTV)-based robust IMPT plans were optimized in 3D on the av_p4DCT and re-calculated on the av_r4DCTs. Re-planning on av_r4DCTs was performed when indicated and accumulated doses were evaluated on the av_p4DCT.Results: Adaptive VMAT and IMPT resulted in adequate ICTV coverage on av_r4DCT in all patients and adequate accumulated-dose ICTV coverage on av_p4DCT in 17/18 patients (due to a shrinking target in one patient). More frequent re-planning was needed for IMPT than for VMAT. The average mean heart dose reduction with IMPT compared with VMAT was 4.6 Gy (p = .001) and it was >5 Gy for five patients (6, 7, 8, 15, and 22 Gy). The average mean lung dose reduction was 3.2 Gy (p < .001). Significant reductions in heart and lung V5 Gy were observed with IMPT.Conclusion: Robust-planned IMPT required re-planning more often than VMAT but resulted in similar accumulated ICTV coverage. With IMPT, heart and lung mean dose values and low dose regions were significantly reduced. Substantial cardiac sparing was obtained in a subgroup of five patients (28%).
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Affiliation(s)
- Hans Paul van der Laan
- Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - R. Melissa Anakotta
- Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Erik W. Korevaar
- Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Margriet Dieters
- Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - J. Fred Ubbels
- Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Robin Wijsman
- Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Nanna M. Sijtsema
- Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Stefan Both
- Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Johannes A. Langendijk
- Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Christina T. Muijs
- Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Antje C. Knopf
- Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
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Korevaar EW, Habraken SJM, Scandurra D, Kierkels RGJ, Unipan M, Eenink MGC, Steenbakkers RJHM, Peeters SG, Zindler JD, Hoogeman M, Langendijk JA. Practical robustness evaluation in radiotherapy - A photon and proton-proof alternative to PTV-based plan evaluation. Radiother Oncol 2019; 141:267-274. [PMID: 31492443 DOI: 10.1016/j.radonc.2019.08.005] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 07/23/2019] [Accepted: 08/10/2019] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND PURPOSE A planning target volume (PTV) in photon treatments aims to ensure that the clinical target volume (CTV) receives adequate dose despite treatment uncertainties. The underlying static dose cloud approximation (the assumption that the dose distribution is invariant to errors) is problematic in intensity modulated proton treatments where range errors should be taken into account as well. The purpose of this work is to introduce a robustness evaluation method that is applicable to photon and proton treatments and is consistent with (historic) PTV-based treatment plan evaluations. MATERIALS AND METHODS The limitation of the static dose cloud approximation was solved in a multi-scenario simulation by explicitly calculating doses for various treatment scenarios that describe possible errors in the treatment course. Setup errors were the same as the CTV-PTV margin and the underlying theory of 3D probability density distributions was extended to 4D to include range errors, maintaining a 90% confidence level. Scenario dose distributions were reduced to voxel-wise minimum and maximum dose distributions; the first to evaluate CTV coverage and the second for hot spots. Acceptance criteria for CTV D98 and D2 were calibrated against PTV-based criteria from historic photon treatment plans. RESULTS CTV D98 in worst case scenario dose and voxel-wise minimum dose showed a very strong correlation with scenario average D98 (R2 > 0.99). The voxel-wise minimum dose visualised CTV dose conformity and coverage in 3D in agreement with PTV-based evaluation in photon therapy. Criteria for CTV D98 and D2 of the voxel-wise minimum and maximum dose showed very strong correlations to PTV D98 and D2 (R2 > 0.99) and on average needed corrections of -0.9% and +2.3%, respectively. CONCLUSIONS A practical approach to robustness evaluation was provided and clinically implemented for PTV-less photon and proton treatment planning, consistent with PTV evaluations but without its static dose cloud approximation.
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Affiliation(s)
- Erik W Korevaar
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands.
| | - Steven J M Habraken
- Holland Proton Therapy Center, Delft, The Netherlands; Department of Radiation Oncology, Erasmus Medical Center Cancer Institute, Rotterdam, The Netherlands
| | - Daniel Scandurra
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands
| | - Roel G J Kierkels
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands
| | - Mirko Unipan
- Proton Therapy Centre South-East Netherlands (ZON-PTC), Maastricht, The Netherlands
| | | | - Roel J H M Steenbakkers
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands
| | - Stephanie G Peeters
- Proton Therapy Centre South-East Netherlands (ZON-PTC), Maastricht, The Netherlands
| | - Jaap D Zindler
- Holland Proton Therapy Center, Delft, The Netherlands; Department of Radiation Oncology, Erasmus Medical Center Cancer Institute, Rotterdam, The Netherlands
| | - Mischa Hoogeman
- Holland Proton Therapy Center, Delft, The Netherlands; Department of Radiation Oncology, Erasmus Medical Center Cancer Institute, Rotterdam, The Netherlands
| | - Johannes A Langendijk
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, The Netherlands
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Guerreiro F, Zachiu C, Seravalli E, Ribeiro CO, Janssens GO, Ries M, de Senneville BD, Maduro JH, Brouwer CL, Korevaar EW, Knopf AC, Raaymakers BW. Evaluating the benefit of PBS vs. VMAT dose distributions in terms of dosimetric sparing and robustness against inter-fraction anatomical changes for pediatric abdominal tumors. Radiother Oncol 2019; 138:158-165. [DOI: 10.1016/j.radonc.2019.06.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 05/27/2019] [Accepted: 06/17/2019] [Indexed: 11/16/2022]
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