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Bennett LC, Hyer DE, Vu J, Patwardhan K, Erhart K, Gutierrez AN, Pons E, Jensen E, Ubau M, Zapata J, Wroe A, Wake K, Nelson NP, Culberson WS, Smith BR, Hill PM, Flynn RT. Patient-specific quality assurance of dynamically-collimated proton therapy treatment plans. Med Phys 2024. [PMID: 38977285 DOI: 10.1002/mp.17295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 05/16/2024] [Accepted: 06/10/2024] [Indexed: 07/10/2024] Open
Abstract
BACKGROUND The dynamic collimation system (DCS) provides energy layer-specific collimation for pencil beam scanning (PBS) proton therapy using two pairs of orthogonal nickel trimmer blades. While excellent measurement-to-calculation agreement has been demonstrated for simple cube-shaped DCS-trimmed dose distributions, no comparison of measurement and dose calculation has been made for patient-specific treatment plans. PURPOSE To validate a patient-specific quality assurance (PSQA) process for DCS-trimmed PBS treatment plans and evaluate the agreement between measured and calculated dose distributions. METHODS Three intracranial patient cases were considered. Standard uncollimated PBS and DCS-collimated treatment plans were generated for each patient using the Astroid treatment planning system (TPS). Plans were recalculated in a water phantom and delivered at the Miami Cancer Institute (MCI) using an Ion Beam Applications (IBA) dedicated nozzle system and prototype DCS. Planar dose measurements were acquired at two depths within low-gradient regions of the target volume using an IBA MatriXX ion chamber array. RESULTS Measured and calculated dose distributions were compared using 2D gamma analysis with 3%/3 mm criteria and low dose threshold of 10% of the maximum dose. Median gamma pass rates across all plans and measurement depths were 99.0% (PBS) and 98.3% (DCS), with a minimum gamma pass rate of 88.5% (PBS) and 91.2% (DCS). CONCLUSIONS The PSQA process has been validated and experimentally verified for DCS-collimated PBS. Dosimetric agreement between the measured and calculated doses was demonstrated to be similar for DCS-collimated PBS to that achievable with noncollimated PBS.
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Affiliation(s)
- Laura C Bennett
- Roy J. Carver Department of Biomedical Engineering, University of Iowa, 5601 Seamans Center for the Engineering Arts and Sciences, Iowa City, Iowa, USA
| | - Daniel E Hyer
- Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | - Justin Vu
- Roy J. Carver Department of Biomedical Engineering, University of Iowa, 5601 Seamans Center for the Engineering Arts and Sciences, Iowa City, Iowa, USA
| | - Kaustubh Patwardhan
- Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | | | - Alonso N Gutierrez
- Department of Radiation Oncology, Miami Cancer Institute, Baptist Health South Florida, Miami, Florida, USA
| | - Eduardo Pons
- Department of Radiation Oncology, Miami Cancer Institute, Baptist Health South Florida, Miami, Florida, USA
| | - Eric Jensen
- Ion Beam Applications S.A., R&D Proton Therapy, Louvain-La-Neuve, Belgium
| | - Manual Ubau
- Ion Beam Applications S.A., R&D Proton Therapy, Louvain-La-Neuve, Belgium
| | - Julio Zapata
- Ion Beam Applications S.A., R&D Proton Therapy, Louvain-La-Neuve, Belgium
| | - Andrew Wroe
- Department of Radiation Oncology, Miami Cancer Institute, Baptist Health South Florida, Miami, Florida, USA
| | - Karsten Wake
- Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA
| | - Nicholas P Nelson
- Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA
- Department of Radiation Oncology, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, USA
| | - Wesley S Culberson
- Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA
| | - Blake R Smith
- Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
| | - Patrick M Hill
- Department of Human Oncology, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA
| | - Ryan T Flynn
- Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA
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Lin Y, Zhang H, Gu S, Shen L, Lv M, Zhang M, Chen Z. Proton beam spot size and position measurements using a multi-strip ionization chamber. Phys Med 2024; 123:103411. [PMID: 38906045 DOI: 10.1016/j.ejmp.2024.103411] [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: 10/07/2023] [Revised: 06/07/2024] [Accepted: 06/11/2024] [Indexed: 06/23/2024] Open
Abstract
PURPOSE To develop and characterize a large-area multi-strip ionization chamber (MSIC) for efficient measurement of proton beam spot size and position at a synchrotron-based proton therapy facility. METHODS AND MATERIALS A 420 mm x 320 mm MSIC was designed with 240 vertical strips and 180 horizontal strips at 1.75 mm pitch. The MSIC was characterized by irradiating a grid of proton spots across 17 energies from 73.5 MeV to 235 MeV and comparing to simultaneous measurements made with a reference Gafchromic EBT3 film. Beam profiles, spot sizes, and positions were analyzed. Short term measurement stability and sensitivity were evaluated. RESULTS Excellent agreement was demonstrated between the MSIC and EBT3 film for both spot size and position measurements. Spot sizes agreed within ± 0.18 mm for all energies tested. Measured beam spot positions agreed within ± 0.17 mm. The detector showed good short term measurement stability and low noise performance. CONCLUSION The large-area MSIC enables efficient and accurate proton beam spot characterization across the clinical energy range. The results indicate the MSIC is suitable for pencil beam scanning proton therapy commissioning and quality assurance applications requiring fast spot size and position quantification.
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Affiliation(s)
- Ye Lin
- Department of Particle Beam Applications, Shanghai Advanced Research Institute, Chinese Academy of Sciences, 201200 Shanghai, China.
| | - Haiqun Zhang
- Department of Particle Beam Applications, Shanghai Advanced Research Institute, Chinese Academy of Sciences, 201200 Shanghai, China
| | - Shuaizhe Gu
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
| | - Liren Shen
- Department of General Technology, Shanghai Advanced Research Institute, Chinese Academy of Sciences, 201200 Shanghai, China
| | - Ming Lv
- Department of Particle Beam Applications, Shanghai Advanced Research Institute, Chinese Academy of Sciences, 201200 Shanghai, China
| | - Manzhou Zhang
- Department of Particle Beam Applications, Shanghai Advanced Research Institute, Chinese Academy of Sciences, 201200 Shanghai, China
| | - Zhiling Chen
- Department of Particle Beam Applications, Shanghai Advanced Research Institute, Chinese Academy of Sciences, 201200 Shanghai, China
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Yaddanapudi S, Wakisaka Y, Furutani KM, Yagi M, Shimizu S, Beltran CJ. Technical Note: Improving the workflow in a carbon ion therapy center with custom software for enhanced patient care. Tech Innov Patient Support Radiat Oncol 2024; 30:100251. [PMID: 38707713 PMCID: PMC11070275 DOI: 10.1016/j.tipsro.2024.100251] [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: 01/22/2024] [Revised: 04/08/2024] [Accepted: 04/19/2024] [Indexed: 05/07/2024] Open
Abstract
Carbon-ion radiation therapy (CIRT) is an up-and-coming modality for cancer treatment. Implementation of CIRT requires collaboration among specialists like radiation oncologists, medical physicists, and other healthcare professionals. Effective communication among team members is necessary for the success of CIRT. However, the current workflows involving data management, treatment planning, scheduling, and quality assurance (QA) can be susceptible to errors, leading to delays and decreased efficiency. With the aim of addressing these challenges, a team of medical physicists developed an in-house workflow management software using FileMaker Pro. This tool has streamlined the workflow and improved the efficiency and quality of patient care.
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Affiliation(s)
| | - Yushi Wakisaka
- Department of Medical Physics and Engineering, Osaka University, Osaka, Japan
- Department of Radiation Technology, Osaka Heavy Ion Therapy Center, Osaka, Japan
| | - Keith M. Furutani
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL, USA
- Department of Carbon Ion Radiotherapy, Osaka University, Osaka, Japan
| | - Masashi Yagi
- Department of Carbon Ion Radiotherapy, Osaka University, Osaka, Japan
| | - Shinichi Shimizu
- Department of Carbon Ion Radiotherapy, Osaka University, Osaka, Japan
| | - Chris J. Beltran
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL, USA
- Department of Carbon Ion Radiotherapy, Osaka University, Osaka, Japan
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Zhang X, Zhang H, Wang J, Ma Y, Liu X, Dai Z, He R, He P, Li Q. Deep learning-based fast denoising of Monte Carlo dose calculation in carbon ion radiotherapy. Med Phys 2023; 50:7314-7323. [PMID: 37656065 DOI: 10.1002/mp.16719] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 08/18/2023] [Accepted: 08/19/2023] [Indexed: 09/02/2023] Open
Abstract
BACKGROUND Plan verification is one of the important steps of quality assurance (QA) in carbon ion radiotherapy. Conventional methods of plan verification are based on phantom measurement, which is labor-intensive and time-consuming. Although the plan verification method based on Monte Carlo (MC) simulation provides a more accurate modeling of the physics, it is also time-consuming when simulating with a large number of particles. Therefore, how to ensure the accuracy of simulation results while reducing simulation time is the current difficulty and focus. PURPOSE The purpose of this work was to evaluate the feasibility of using deep learning-based MC denoising method to accelerate carbon-ion radiotherapy plan verification. METHODS Three models, including CycleGAN, 3DUNet and GhostUNet with Ghost module, were used to denoise the 1 × 106 carbon ions-based MC dose distribution to the accuracy of 1 × 108 carbon ions-based dose distribution. The CycleGAN's generator, 3DUNet and GhostUNet were all derived from the 3DUNet network. A total of 59 cases including 29 patients with head-and-neck cancers and 30 patients with lung cancers were collected, and 48 cases were randomly selected as the training set of the CycleGAN network and six cases as the test set. For the 3DUNet and GhostUNet models, the numbers of training set, validation set, and test set were 47, 6, and 6, respectively. Finally, the three models were evaluated qualitatively and quantitatively using RMSE and three-dimensional gamma analysis (3 mm, 3%). RESULTS The three end-to-end trained models could be used for denoising the 1 × 106 carbon ions-based dose distribution, and their generalization was proved. The GhostUNet obtained the lowest RMSE value of 0.075, indicating the smallest difference between its denoised and 1 × 108 carbon ions-based dose distributions. The average gamma passing rate (GPR) between the GhostUNet denoising-based versus 1 × 108 carbon ions-based dose distributions was 99.1%, higher than that of the CycleGAN at 94.3% and the 3DUNet at 96.2%. Among the three models, the GhostUNet model had the fewest parameters (4.27 million) and the shortest training time (99 s per epoch) but achieved the best denoising results. CONCLUSION The end-to-end deep network GhostUNet outperforms the CycleGAN, 3DUNet models in denoising MC dose distributions for carbon ion radiotherapy. The network requires less than 5 s to denoise a sample of MC simulation with few particles to obtain a qualitative and quantitative result comparable to the dose distribution simulated by MC with relatively large number particles, offering a significant reduction in computation time.
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Affiliation(s)
- Xinyang Zhang
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Hui Zhang
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou, China
- Putian Lanhai Nuclear Medicine Research Center, Putian, China
| | - Jian Wang
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yuanyuan Ma
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou, China
- Putian Lanhai Nuclear Medicine Research Center, Putian, China
| | - Xinguo Liu
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou, China
- Putian Lanhai Nuclear Medicine Research Center, Putian, China
| | - Zhongying Dai
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou, China
- Putian Lanhai Nuclear Medicine Research Center, Putian, China
| | - Rui He
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China
- School of Nuclear Science and Technology, Lanzhou University, Lanzhou, China
| | - Pengbo He
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou, China
- Putian Lanhai Nuclear Medicine Research Center, Putian, China
| | - Qiang Li
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou, China
- Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou, China
- University of Chinese Academy of Sciences, Beijing, China
- Putian Lanhai Nuclear Medicine Research Center, Putian, China
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5
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Jeon C, Lee J, Shin J, Cheon W, Ahn S, Jo K, Han Y. Monte Carlo simulation-based patient-specific QA using machine log files for line-scanning proton radiation therapy. Med Phys 2023; 50:7139-7153. [PMID: 37756652 DOI: 10.1002/mp.16747] [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: 10/31/2022] [Revised: 09/05/2023] [Accepted: 09/06/2023] [Indexed: 09/29/2023] Open
Abstract
BACKGROUND Quality assurance (QA) is a prerequisite for safe and accurate pencil-beam proton therapy. Conventional measurement-based patient-specific QA (pQA) can only verify limited aspects of patient treatment and is labor-intensive. Thus, a better method is needed to ensure the integrity of the treatment plan. PURPOSE Line scanning, which involves continuous and rapid delivery of pencil beams, is a state-of-the-art proton therapy technique. Machine performance in delivering scanning protons is dependent on the complexity of the beam modulations. Moreover, it contributes to patient treatment accuracy. A Monte Carlo (MC) simulation-based QA method that reflects the uncertainty related to the machine during scanning beam delivery was developed and verified for clinical applications to pQA. METHODS Herein, a tool for particle simulation (TOPAS) for nozzle modeling was used, and the code was commissioned against the measurements. To acquire the beam delivery uncertainty for each plan, patient plans were delivered. Furthermore, log files recorded every 60 μs by the monitors downstream of the nozzle were exported from the treatment control system. The spot positions and monitor unit (MU) counts in the log files were converted to dipole magnet strengths and number of particles, respectively, and entered into the TOPAS. For the 68 clinical cases, MC simulations were performed in a solid water phantom, and two-dimensional (2D) absolute dose distributions at 20-mm depth were measured using an ionization chamber array (Octavius 1500, PTW, Freiburg, Germany). Consequently, the MC-simulated 2D dose distributions were compared with the measured data, and the dose distributions in the pre-treatment QA plan created with RayStation (RaySearch Laboratories, Stockholm, Sweden). Absolute dose comparisons were made using gamma analysis with 3%/3 mm and 2%/2 mm criteria for 47 clinical cases without considering daily machine output variation in the MC simulation and 21 cases with daily output variation, respectively. All cases were analyzed with 90% or 95% of passing rate thresholds. RESULTS For 47 clinical cases not considering daily output variations, the absolute gamma passing rates compared with the pre-treatment QA plan were 99.71% and 96.97%, and the standard deviations (SD) were 0.70% and 3.78% with the 3%/3 mm or 2%/2 mm criteria, respectively. Compared with the measurements, the passing rate of 2%/2 mm gamma criterion was 96.76% with 3.99% of SD. For the 21 clinical cases compared with pre-treatment QA plan data and measurements considering daily output variations, the 2%/2 mm absolute gamma analysis result was 98.52% with 1.43% of SD and 97.67% with 2.72% of SD, respectively. With a 95% passing rate threshold of 2%/2 mm criterion, the false-positive and false-negative were 21.8% and 8.3% for without and with considering output variation, respectively. With a 90% threshold, the false-positive and false-negative reduced to 11.4% and 0% for without and with considering output variation, respectively. CONCLUSIONS A log-file-based MC simulation method for patient QA of line-scanning proton therapy was successfully developed. The proposed method exhibited clinically acceptable accuracy, thereby exhibiting a potential to replace the measurement-based dosimetry QA method with a 90% gamma passing rate threshold when applying the 2%/2 mm criterion.
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Affiliation(s)
- Chanil Jeon
- Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Republic of Korea
| | - Jinhyeop Lee
- Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Republic of Korea
| | - Jungwook Shin
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institute of Health, Rockville, Maryland, USA
| | - Wonjoong Cheon
- Department of Radiation Oncology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Sunghwan Ahn
- Department of Radiation Oncology, Samsung Medical Center, Seoul, Republic of Korea
| | - Kwanghyun Jo
- Department of Radiation Oncology, Samsung Medical Center, Seoul, Republic of Korea
| | - Youngyih Han
- Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Republic of Korea
- Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Republic of Korea
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Miyazaki K, Fujii Y, Yamada T, Kanehira T, Miyamoto N, Matsuura T, Yasuda K, Uchinami Y, Otsuka M, Aoyama H, Takao S. Deformed dose restoration to account for tumor deformation and position changes for adaptive proton therapy. Med Phys 2023; 50:675-687. [PMID: 36502527 DOI: 10.1002/mp.16149] [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: 08/18/2022] [Revised: 11/10/2022] [Accepted: 11/25/2022] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Online adaptation during intensity-modulated proton therapy (IMPT) can minimize the effect of inter-fractional anatomical changes, but remains challenging because of the complex workflow. One approach for fast and automated online IMPT adaptation is dose restoration, which restores the initial dose distribution on the updated anatomy. However, this method may fail in cases where tumor deformation or position changes occur. PURPOSE To develop a fast and robust IMPT online adaptation method named "deformed dose restoration (DDR)" that can adjust for inter-fractional tumor deformation and position changes. METHODS The DDR method comprises two steps: (1) calculation of the deformed dose distribution, and (2) restoration of the deformed dose distribution. First, the deformable image registration (DIR) between the initial clinical target volume (CTV) and the new CTV were performed to calculate the vector field. To ensure robustness for setup and range uncertainty and the ability to restore the deformed dose distribution, an expanded CTV-based registration to maintain the dose gradient outside the CTV was developed. The deformed dose distribution was obtained by applying the vector field to the initial dose distribution. Then, the voxel-by-voxel dose difference optimization was performed to calculate beam parameters that restore the deformed dose distribution on the updated anatomy. The optimization function was the sum of total dose differences and dose differences of each field to restore the initial dose overlap of each field. This method only requires target contouring, which eliminates the need for organs at risk (OARs) contouring. Six clinical cases wherein the tumor deformation and/or position changed on repeated CTs were selected. DDR feasibility was evaluated by comparing the results with those from three other strategies, namely, not adapted (continuing the initial plan), adapted by previous dose restoration, and fully optimized. RESULTS In all cases, continuing the initial plan was largely distorted on the repeated CTs and the dose-volume histogram (DVH) metrics for the target were reduced due to the tumor deformation or position changes. On the other hand, DDR improved DVH metrics for the target to the same level as the initial dose distribution. Dose increase was seen for some OARs because tumor growth had reduced the relative distance between CTVs and OARs. Robustness evaluation for setup and range uncertainty (3 mm/3.5%) showed that deviation in DVH-bandwidth for CTV D95% from the initial plan was 0.4% ± 0.5% (Mean ± S.D.) for DDR. The calculation time was 8.1 ± 6.4 min. CONCLUSIONS An online adaptation algorithm was developed that improved the treatment quality for inter-fractional anatomical changes and retained robustness for intra-fractional setup and range uncertainty. The main advantage of this method is that it only requires target contouring alone and saves the time for OARs contouring. The fast and robust adaptation method for tumor deformation and position changes described here can reduce the need for offline adaptation and improve treatment efficiency.
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Affiliation(s)
- Koichi Miyazaki
- Graduate School of Biomedical Science and Engineering, Hokkaido University, Sapporo, Hokkaido, Japan.,Department of Medical Physics, Hokkaido University Hospital, Sapporo, Hokkaido, Japan.,Research and Development Group, Hitachi Ltd, Hitachi, Ibaraki, Japan
| | - Yusuke Fujii
- Research and Development Group, Hitachi Ltd, Hitachi, Ibaraki, Japan
| | - Takahiro Yamada
- Research and Development Group, Hitachi Ltd, Hitachi, Ibaraki, Japan
| | - Takahiro Kanehira
- Department of Medical Physics, Hokkaido University Hospital, Sapporo, Hokkaido, Japan
| | - Naoki Miyamoto
- Department of Medical Physics, Hokkaido University Hospital, Sapporo, Hokkaido, Japan.,Division of Quantum Science and Engineering, Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Taeko Matsuura
- Department of Medical Physics, Hokkaido University Hospital, Sapporo, Hokkaido, Japan.,Division of Quantum Science and Engineering, Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Koichi Yasuda
- Department of Radiation Oncology, Faculty of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Yusuke Uchinami
- Department of Radiation Oncology, Faculty of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Manami Otsuka
- Department of Radiation Oncology, Faculty of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Hidefumi Aoyama
- Department of Radiation Oncology, Faculty of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Seishin Takao
- Department of Medical Physics, Hokkaido University Hospital, Sapporo, Hokkaido, Japan.,Division of Quantum Science and Engineering, Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido, Japan.,Global Center for Biomedical Science and Engineering, Faculty of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
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Magro G, Fassi M, Mirandola A, Rossi E, Molinelli S, Russo S, Bazani A, Vai A, Ciocca M, Donetti M, Mairani A. Dosimetric validation of a GPU-based dose engine for a fast in silico patient-specific quality assurance program in light ion beam therapy. Med Phys 2022; 49:7802-7814. [PMID: 36196033 DOI: 10.1002/mp.16002] [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: 06/03/2022] [Revised: 09/16/2022] [Accepted: 09/17/2022] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND With rapid evolutions of fast and sophisticated calculation techniques and delivery technologies, clinics are almost facing a daily patient-specific (PS) plan adaptation, which would make a conventional experimental quality assurance (QA) workflow unlikely to be routinely feasible. Therefore, in silico approaches are foreseen by means of second-check independent dose calculation systems possibly handling machine log-files. PURPOSE To validate the in-house developed GPU-dose engine, FRoG, for light ion beam therapy (protons and carbon ions) as a second-check independent calculation system and to integrate machine log-file analysis into the patient-specific quality assurance (PSQA) program. METHODS Spot sizes, depth-dose distributions, and absolute dose calibrations were configured into FRoG and a set of nine regular-shaped targets in combination with more than 170 clinical treatment fields were tested against pinpoint ionization chamber measurements. Both the treatment planning system DICOM RTplans and machine treatment log-files were used as input for the dose kernel in water, and a 3D local γ (1 mm/2%) index was used as the main evaluation metric. RESULTS Calculated configuration data matched experimental measurements with submillimetric agreement. For regular-shaped targets, the unsigned average relative difference between calculated and measured dose values was less than 2% for both protons and carbon ions. The mean γ passing rate (PR) was around 98% for both particle species. For clinical treatment beams, DICOM-based recalculations showed a γ-PR more than 99% for both particle species. The same level of agreement was preserved for protons when moving to log-file-based recalculations. A score of around 95% was registered for carbon ion beams, once excluding low-quality machine log-files. Unsigned average relative difference against acquired data was less than 2% also for real clinical beams. CONCLUSIONS FRoG was proven as an accurate and reliable tool for PSQA in scanning light ion beam therapy. The proposed method allows for an extremely efficient workflow, without compromising the quality of the plan verification procedure.
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Affiliation(s)
- Giuseppe Magro
- Clinical Department Medical Physics Unit, Italian National Center for Oncological Hadrontherapy (CNAO Foundation), Pavia, Italy
| | - Martina Fassi
- Department of Physics, University of Milan-Bicocca, Milan, Italy
| | - Alfredo Mirandola
- Clinical Department Medical Physics Unit, Italian National Center for Oncological Hadrontherapy (CNAO Foundation), Pavia, Italy
| | - Eleonora Rossi
- Clinical Department Medical Physics Unit, Italian National Center for Oncological Hadrontherapy (CNAO Foundation), Pavia, Italy
| | - Silvia Molinelli
- Clinical Department Medical Physics Unit, Italian National Center for Oncological Hadrontherapy (CNAO Foundation), Pavia, Italy
| | - Stefania Russo
- Clinical Department Medical Physics Unit, Italian National Center for Oncological Hadrontherapy (CNAO Foundation), Pavia, Italy
| | - Alessia Bazani
- Clinical Department Medical Physics Unit, Italian National Center for Oncological Hadrontherapy (CNAO Foundation), Pavia, Italy
| | - Alessandro Vai
- Clinical Department Medical Physics Unit, Italian National Center for Oncological Hadrontherapy (CNAO Foundation), Pavia, Italy
| | - Mario Ciocca
- Clinical Department Medical Physics Unit, Italian National Center for Oncological Hadrontherapy (CNAO Foundation), Pavia, Italy
| | - Marco Donetti
- Clinical Department Medical Physics Unit, Italian National Center for Oncological Hadrontherapy (CNAO Foundation), Pavia, Italy
| | - Andrea Mairani
- Clinical Department Medical Physics Unit, Italian National Center for Oncological Hadrontherapy (CNAO Foundation), Pavia, Italy.,Department of Radiation Oncology, Heidelberg Ion-Beam Therapy Center (HIT), Heidelberg University Hospital, Heidelberg, Germany
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8
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A plan verification platform for online adaptive proton therapy using deep learning-based Monte–Carlo denoising. Phys Med 2022; 103:18-25. [DOI: 10.1016/j.ejmp.2022.09.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 09/27/2022] [Accepted: 09/28/2022] [Indexed: 11/21/2022] Open
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9
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Feng H, Patel SH, Wong WW, Younkin JE, Penoncello GP, Morales DH, Stoker JB, Robertson DG, Fatyga M, Bues M, Schild SE, Foote RL, Liu W. GPU-accelerated Monte Carlo-based online adaptive proton therapy - a feasibility study. Med Phys 2022; 49:3550-3563. [PMID: 35443080 DOI: 10.1002/mp.15678] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 03/21/2022] [Accepted: 04/12/2022] [Indexed: 11/06/2022] Open
Abstract
PURPOSE To develop an online Graphic-Processing-Unit (GPU)-accelerated Monte-Carlo-based adaptive radiation therapy (ART) workflow for pencil beam scanning (PBS) proton therapy to address inter-fraction anatomical changes in patients treated with PBS. METHODS AND MATERIALS A four-step workflow was developed using our in-house developed GPU-accelerated Monte-Carlo-based treatment planning system to implement online Monte-Carlo-based ART for PBS. The first step conducts diffeomorphic demon-based deformable image registration (DIR) to propagate contours on the initial planning CT (pCT) to the verification CT (vCT) to form a new structure set. The second step performs forward dose calculation of the initial plan on the vCT with the propagated contours after manual approval (possible modifications involved). The third step triggers a re-optimization of the plan depending on whether the verification dose meets the clinical requirements or not. A robust evaluation will be done for both the verification plan in the second step and the re-opotimized plan in the third step. The fourth step involves a two-stage (before and after delivery) patient specific quality assurance (PSQA) of the re-optimized plan. The before-delivery PSQA is to compare the plan dose to the dose calculated using an independent fast open-source Monte Carlo code, MCsquare. The after-delivery PSQA is to compare the plan dose to the dose re-calculated using the log file (spot MU, spot position, and spot energy) collected during the delivery. Jaccard index (JI), Dice similarity coefficients (DSCs), and Hausdorff distance (HD) were used to assess the quality of the propagated contours in the first step. A commercial plan evaluation software, ClearCheck™, was integrated into the workflow to carry out efficient plan evaluation. 3D Gamma analysis was used during the fourth step to ensure the accuracy of the plan dose from re-optimization. Three patients with three different disease sites were chosen to evaluate the feasibility of the online ART workflow for PBS. RESULTS For all three patients, the propagated contours were found to have good volume conformance [JI (lowest-highest: 0.833-0.983) and DSC (0.909-0.992)] but sub-optimal boundary coincidence [HD (2.37-20.76 mm)] for organs at risk (OARs). The verification dose evaluated by ClearCheck™ showed significant degradation of the target coverage due to the inter-fractional anatomical changes. Re-optimization on the vCT resulted in great improvement of the plan quality to a clinically acceptable level. 3D Gamma analyses of PSQA confirmed the accuracy of the plan dose before delivery (mean Gamma index = 98.74% with a threshold of 2%/2 mm/10%), and after delivery based on the log files (mean Gamma index = 99.05% with a threshold of 2%/2 mm/10%). The average time cost for the complete execution of the workflow was around 858 seconds, excluding the time for manual intervention. CONCLUSION The proposed online ART workflow for PBS was demonstrated to be efficient and effective by generating a re-optimized plan that significantly improved the plan quality. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Hongying Feng
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - Samir H Patel
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - William W Wong
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - James E Younkin
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | | | | | - Joshua B Stoker
- 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
| | - Steven E Schild
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - Robert L Foote
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN, 55902, USA
| | - Wei Liu
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
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10
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Paganetti H, Botas P, Sharp GC, Winey B. Adaptive proton therapy. Phys Med Biol 2021; 66:10.1088/1361-6560/ac344f. [PMID: 34710858 PMCID: PMC8628198 DOI: 10.1088/1361-6560/ac344f] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 10/28/2021] [Indexed: 12/25/2022]
Abstract
Radiation therapy treatments are typically planned based on a single image set, assuming that the patient's anatomy and its position relative to the delivery system remains constant during the course of treatment. Similarly, the prescription dose assumes constant biological dose-response over the treatment course. However, variations can and do occur on multiple time scales. For treatment sites with significant intra-fractional motion, geometric changes happen over seconds or minutes, while biological considerations change over days or weeks. At an intermediate timescale, geometric changes occur between daily treatment fractions. Adaptive radiation therapy is applied to consider changes in patient anatomy during the course of fractionated treatment delivery. While traditionally adaptation has been done off-line with replanning based on new CT images, online treatment adaptation based on on-board imaging has gained momentum in recent years due to advanced imaging techniques combined with treatment delivery systems. Adaptation is particularly important in proton therapy where small changes in patient anatomy can lead to significant dose perturbations due to the dose conformality and finite range of proton beams. This review summarizes the current state-of-the-art of on-line adaptive proton therapy and identifies areas requiring further research.
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Affiliation(s)
- Harald Paganetti
- Department of Radiation Oncology, Physics Division, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
| | - Pablo Botas
- Department of Radiation Oncology, Physics Division, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
- Foundation 29 of February, Pozuelo de Alarcón, Madrid, Spain
| | - Gregory C Sharp
- Department of Radiation Oncology, Physics Division, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
| | - Brian Winey
- Department of Radiation Oncology, Physics Division, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
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11
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Ricci JC, Hsi WC, Su Z, Mund K, Dawson R, Indelicato DJ. The root cause analysis on failed patient-specific measurements of pencil beam scanning protons using a 2D detection array with finite size ionization chambers. J Appl Clin Med Phys 2021; 22:175-190. [PMID: 34312997 PMCID: PMC8364270 DOI: 10.1002/acm2.13343] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 04/21/2021] [Accepted: 06/03/2021] [Indexed: 02/01/2023] Open
Abstract
The aim of this report is to present the root cause analysis on failed patient‐specific quality assurance (QA) measurements of pencil beam scanning (PBS) protons; referred to as PBS‐QA measurement. A criterion to fail a PBS‐QA measurement is having a <95% passing rate in a 3.0%‐3.0 mm gamma index analysis. Clinically, we use a two‐dimensional (2D) gamma index analysis to obtain the passing rate. The IBA MatriXX PT 2D detection array with finite size ionization chamber was utilized. A total of 2488 measurements performed in our PBS beamline were cataloged. The percentage of measurements for the sites of head/neck, breast, prostate, and other are 53.3%, 22.7%, 10.5%, and 13.5%, respectively. The measurements with a passing rate of 100 to >94%, 94 to >88%, and <88% were 93.6%, 5.6%, and 0.8%, respectively. The percentage of failed measurements with a <95% passing rate was 10.9%. After removed the user errors of either re‐measurement or re‐analysis, 8.1% became acceptable. We observed a feature of >3% per mm dose gradient with respect to depth on the failed measurements. We utilized a 2D/three‐dimensional (3D) gamma index analysis toolkit to investigate the effect of depth dose gradient. By utilizing this 3D toolkit, 43.1% of the failed measurements were improved. A feature among measurements that remained sub‐optimal after re‐analysis was a sharp >3% per mm lateral dose gradient that may not be well handled using the detector size of 5.0 mm in‐diameter. An analysis of the sampling of finite size detectors using one‐dimensional (1D) error function showed a large dose deviation at locations of low‐dose areas between two high‐dose plateaus. User error, large depth dose gradient, and the effect of detector size are identified as root causes. With the mitigation of the root causes, the goals of patient‐specific QA, specifically detecting actual deviation of beam delivery or identifying limitations of the dose calculation algorithm of the treatment planning system, can be directly related to failure of the PBS‐QA measurements.
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Affiliation(s)
- Jacob C Ricci
- Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL, USA.,Department of Radiation Oncology, University of Florida Health Proton Therapy Institute, Jacksonville, FL, USA
| | - Wen C Hsi
- Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL, USA.,Department of Radiation Oncology, University of Florida Health Proton Therapy Institute, Jacksonville, FL, USA
| | - Zhong Su
- Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL, USA.,Department of Radiation Oncology, University of Florida Health Proton Therapy Institute, Jacksonville, FL, USA
| | - Karl Mund
- Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL, USA
| | - Robert Dawson
- Department of Medical Physics, University of Florida College of Medicine, Gainesville, FL, USA.,Department of Radiation Oncology, Ackerman Cancer Center, Jacksonville, FL, USA
| | - Daniel J Indelicato
- Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL, USA.,Department of Radiation Oncology, University of Florida Health Proton Therapy Institute, Jacksonville, FL, USA
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12
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Yamada T, Takao S, Koyano H, Nihongi H, Fujii Y, Hirayama S, Miyamoto N, Matsuura T, Umegaki K, Katoh N, Yokota I, Shirato H, Shimizu S. Validation of dose distribution for liver tumors treated with real-time-image gated spot-scanning proton therapy by log data based dose reconstruction. JOURNAL OF RADIATION RESEARCH 2021; 62:626-633. [PMID: 33948661 PMCID: PMC8273791 DOI: 10.1093/jrr/rrab024] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/02/2020] [Indexed: 06/12/2023]
Abstract
In spot scanning proton therapy (SSPT), the spot position relative to the target may fluctuate through tumor motion even when gating the radiation by utilizing a fiducial marker. We have established a procedure that evaluates the delivered dose distribution by utilizing log data on tumor motion and spot information. The purpose of this study is to show the reliability of the dose distributions for liver tumors treated with real-time-image gated SSPT (RGPT). In the evaluation procedure, the delivered spot information and the marker position are synchronized on the basis of log data on the timing of the spot irradiation and fluoroscopic X-ray irradiation. Then a treatment planning system reconstructs the delivered dose distribution. Dose distributions accumulated for all fractions were reconstructed for eight liver cases. The log data were acquired in all 168 fractions for all eight cases. The evaluation was performed for the values of maximum dose, minimum dose, D99, and D5-D95 for the clinical target volumes (CTVs) and mean liver dose (MLD) scaled by the prescribed dose. These dosimetric parameters were statistically compared between the planned dose distribution and the reconstructed dose distribution. The mean difference of the maximum dose was 1.3% (95% confidence interval [CI]: 0.6%-2.1%). Regarding the minimum dose, the mean difference was 0.1% (95% CI: -0.5%-0.7%). The mean differences of D99, D5-D95 and MLD were below 1%. The reliability of dose distributions for liver tumors treated with RGPT-SSPT was shown by the evaluation of the accumulated dose distributions.
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Affiliation(s)
- Takahiro Yamada
- Hitachi Ltd. 1-1 7-chome, Oomika-cho, Hitachi-shi, Ibaraki 319-1292, Japan
- Graduate School of Biomedical Science and Engineering, Hokkaido University, North15 West7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
| | - Seishin Takao
- Corresponding author. Seishin Takao, Department of Medical Physics, Hokkaido University Hospital, North14 West5, Kita-ku, Sapporo, Hokkaido 060-8638, Japan, Tel: (+81)11-706-5254, Fax: (+81) 11-706-5255, E-mail address:
| | - Hidenori Koyano
- Department of Medical Physics, Graduate School of Medicine, Hokkaido University, North15 West7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
| | - Hideaki Nihongi
- Hitachi Ltd. 1-1 7-chome, Oomika-cho, Hitachi-shi, Ibaraki 319-1292, Japan
| | - Yusuke Fujii
- Hitachi Ltd. 1-1 7-chome, Oomika-cho, Hitachi-shi, Ibaraki 319-1292, Japan
| | - Shusuke Hirayama
- Hitachi Ltd. 1-1 7-chome, Oomika-cho, Hitachi-shi, Ibaraki 319-1292, Japan
- Graduate School of Biomedical Science and Engineering, Hokkaido University, North15 West7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
| | - Naoki Miyamoto
- Department of Medical Physics, Hokkaido University Hospital, North14 West5, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
- Division of Quantum Science and Engineering, Faculty of Engineering, Hokkaido University, North13 West8, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
- Global Station of Quantum Medical Science and Engineering, Global Institution for Collaborative Research and Education, Hokkaido University, North15 West7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
| | - Taeko Matsuura
- Department of Medical Physics, Hokkaido University Hospital, North14 West5, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
- Division of Quantum Science and Engineering, Faculty of Engineering, Hokkaido University, North13 West8, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
- Global Station of Quantum Medical Science and Engineering, Global Institution for Collaborative Research and Education, Hokkaido University, North15 West7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
| | - Kikuo Umegaki
- Department of Medical Physics, Hokkaido University Hospital, North14 West5, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
- Division of Quantum Science and Engineering, Faculty of Engineering, Hokkaido University, North13 West8, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
- Global Station of Quantum Medical Science and Engineering, Global Institution for Collaborative Research and Education, Hokkaido University, North15 West7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
| | - Norio Katoh
- Global Station of Quantum Medical Science and Engineering, Global Institution for Collaborative Research and Education, Hokkaido University, North15 West7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
- Department of Therapeutic Radiology, Faculty of Medicine, Hokkaido University, North15 West7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
| | - Isao Yokota
- Department of Biostatistics, Graduate School of Medicine, Hokkaido University, North15 West7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
| | - Hiroki Shirato
- Global Station of Quantum Medical Science and Engineering, Global Institution for Collaborative Research and Education, Hokkaido University, North15 West7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
- Department of Proton Beam Therapy, Faculty of Medicine, Hokkaido University, North15 West7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
| | - Shinichi Shimizu
- Department of Medical Physics, Hokkaido University Hospital, North14 West5, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
- Global Station of Quantum Medical Science and Engineering, Global Institution for Collaborative Research and Education, Hokkaido University, North15 West7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
- Department of Radiation Medical Science and Engineering, Faculty of Medicine, Hokkaido University, North15 West7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
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13
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Gunn GB, Garden AS, Ye R, Ausat N, Dahlstrom KR, Morrison WH, Fuller CD, Phan J, Reddy JP, Shah SJ, Mayo LL, Chun SG, Chronowski GM, Moreno AC, Myers JN, Hanna EY, Esmaeli B, Gillison ML, Ferrarotto R, Hutcheson KA, Chambers MS, Ginsberg LE, El-Naggar AK, Rosenthal DI, Zhu XR, Frank SJ. Proton Therapy for Head and Neck Cancer: A 12-Year, Single-Institution Experience. Int J Part Ther 2021; 8:108-118. [PMID: 34285940 PMCID: PMC8270083 DOI: 10.14338/ijpt-20-00065.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 11/02/2020] [Indexed: 02/03/2023] Open
Abstract
PURPOSE To characterize our experience and the disease control and toxicity of proton therapy (PT) for patients with head and neck cancer (HNC). PATIENTS AND METHODS Clinical outcomes for patients with HNC treated with PT at our institution were prospectively collected in 2 institutional review board-approved prospective studies. Descriptive statistics were used to summarize patient characteristics and outcomes. Overall survival, local-regional control, and disease-free survival were estimated by the Kaplan-Meier method. Treatment-related toxicities were recorded according to the Common Terminology Criteria for Adverse Events (version 4.03) scale. RESULTS The cohort consisted of 573 patients treated from February 2006 to June 2018. Median patient age was 61 years. Oropharynx (33.3%; n = 191), paranasal sinus (11%; n = 63), and periorbital tissues (11%; n = 62) were the most common primary sites. Patients with T3/T4 or recurrent disease comprised 46% (n = 262) of the cohort. The intent of PT was definitive in 53% (n = 303), postoperative in 37% (n = 211), and reirradiation in 10% (n = 59). Median dose was 66 Gy (radiobiological equivalent). Regarding systemic therapy, 43% had received concurrent (n = 244), 3% induction (n = 19), and 15% (n = 86) had both. At a median follow-up of 2.4 years, 88 patients (15%) had died and 127 (22%) developed disease recurrence. The overall survival, local-regional control, and disease-free survival at 2 and 5 years were, respectively, 87% and 75%, 87% and 78%, and 74% and 63%. Maximum toxicity (acute or late) was grade 3 in 293 patients (51%), grade 2 in 234 patients (41%), and grade 1 in 31 patients (5%). There were 381 acute grade 3 and 190 late grade 3 unique toxicities across 212 (37%) and 150 (26%) patients, respectively. There were 3 late-grade 4 events across 2 patients (0.3%), 2 (0.3%) acute-grade 5, and no (0%) late-grade 5 events. CONCLUSIONS The overall results from this prospective study of our initial decade of experience with PT for HNC show favorable disease control and toxicity outcomes in a multidisease-site cohort and provide a reference benchmark for future comparison and study.
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Affiliation(s)
- G. Brandon Gunn
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Adam S. Garden
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Rong Ye
- Department of Biostatistics, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Noveen Ausat
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Kristina R. Dahlstrom
- Department of Head and Neck Surgery, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - William H. Morrison
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - C. David Fuller
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jack Phan
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jay P. Reddy
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Shalin J. Shah
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Lauren L. Mayo
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Stephen G. Chun
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Gregory M. Chronowski
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Amy C. Moreno
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jeffery N. Myers
- Department of Head and Neck Surgery, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Ehab Y. Hanna
- Department of Head and Neck Surgery, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Bita Esmaeli
- Ophthalmic Plastic Surgery, Department of Plastic Surgery, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Maura L. Gillison
- Department of Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Renata Ferrarotto
- Department of Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Katherine A. Hutcheson
- Department of Head and Neck Surgery, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Mark S. Chambers
- Department of Head and Neck Surgery, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Lawrence E. Ginsberg
- Department of Neuroradiology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Adel K. El-Naggar
- Department of Pathology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - David I. Rosenthal
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Xiaorong Ronald Zhu
- Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Steven J. Frank
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
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14
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Zhao J, Chen Z, Wu X, Xing Y, Li Y. Study of an Online Plan Verification Method and the Sensitivity of Plan Delivery Accuracy to Different Beam Parameter Errors in Proton and Carbon Ion Radiotherapy. Front Oncol 2021; 11:666141. [PMID: 34123830 PMCID: PMC8193983 DOI: 10.3389/fonc.2021.666141] [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: 02/09/2021] [Accepted: 05/04/2021] [Indexed: 11/13/2022] Open
Abstract
For scanning beam particle therapy, the plan delivery accuracy is affected by spot size deviation, position deviation and particle number deviation. Until now, all plan verification systems available for particle therapy have been designed for pretreatment verification. The purpose of this study is to introduce a method for online plan delivery accuracy checks and to evaluate the sensitivity of plan delivery accuracy to different beam parameter errors. A program was developed using MATLAB to reconstruct doses from beam parameters recorded in log files and to compare them with the doses calculated by treatment planning system (TPS). Both carbon ion plans and proton plans were evaluated in this study. The dose reconstruction algorithm is verified by comparing the dose from the TPS with the reconstructed dose under the same beam parameters. The sensitivity of plan delivery accuracy to different beam parameter errors was analyzed by comparing the dose reconstructed from the pseudo plans that manually added errors with the original plan dose. For the validation of dose reconstruction algorithm, mean dose difference between the reconstructed dose and the plan dose were 0.70% ± 0.24% and 0.51% ± 0.25% for carbon ion beam and proton beam, respectively. According to our simulation, the delivery accuracy of the carbon ion plan is more sensitive to spot position deviation and particle number deviation, and the delivery accuracy of the proton plan is more sensitive to spot size deviation. To achieve a 90% gamma pass rate with 3 mm/3% criteria, the average spot size deviation, position deviation, particle number deviation should be within 23%, 1.9 mm, and 1.5% and 20%, 2.1 mm, and 1.6% for carbon ion beam and proton beam, respectively. In conclusion, the method that we introduced for online plan delivery verification is feasible and reliable. The sensitivity of plan delivery accuracy to different errors was clarified for our system. The methods used in this study can be easily repeated in other particle therapy centers.
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Affiliation(s)
- Jun Zhao
- Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Radiation Oncology, Shanghai, China.,Department of Medical Physics, Shanghai Proton and Heavy Ion Center, Shanghai, China
| | - Zhi Chen
- Department of Medical Physics, Shanghai Proton and Heavy Ion Center, Shanghai, China
| | - Xianwei Wu
- Department of Medical Physics, Shanghai Proton and Heavy Ion Center, Shanghai, China
| | - Ying Xing
- Department of Medical Physics, Shanghai Proton and Heavy Ion Center, Shanghai, China
| | - Yongqiang Li
- Department of Medical Physics, Shanghai Proton and Heavy Ion Center, Shanghai, China
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15
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Intensity-modulated proton therapy for oropharyngeal cancer reduces rates of late xerostomia. Radiother Oncol 2021; 160:32-39. [PMID: 33839202 DOI: 10.1016/j.radonc.2021.03.036] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 03/23/2021] [Accepted: 03/28/2021] [Indexed: 01/13/2023]
Abstract
BACKGROUND AND PURPOSE To determine rates of xerostomia after intensity-modulated radiotherapy (IMRT) or intensity-modulated proton therapy (IMPT) for oropharyngeal cancer (OPC) and identify dosimetric factors associated with xerostomia risk. MATERIALS AND METHODS Patients with OPC who received IMRT (n = 429) or IMPT (n = 103) from January 2011 through June 2015 at a single institution were studied retrospectively. Every 3 months after treatment, each patient completed an eight-item self-reported xerostomia-specific questionnaire (XQ; summary XQ score, 0-100). An XQ score of 50 was selected as the demarcation value for moderate-severe (XQs ≥ 50) and no-mild (XQs < 50) xerostomia. The mean doses and percent volumes of organs at risk receiving various doses (V5-V70) were extracted from the initial treatment plans. The dosimetric variables and xerostomia risk were compared using an independent-sample t-test or chi-square test. RESULTS The median follow-up time was 36.2 months. The proportions of patients with moderate-severe xerostomia were similar in the two treatment groups up to 18 months after treatment. However, moderate-severe xerostomia was less common in the IMPT group than in the IMRT group at 18-24 months (6% vs. 20%; p = 0.025) and 24-36 months (6% vs. 20%; p = 0.01). During the late xerostomia period (24-36 months), high dose/volume exposures (V25-V70) in the oral cavity were associated with high proportions of patients with moderate-severe xerostomia (all p < 0.05), but dosimetric variables regarding the salivary glands were not associated with late xerostomia. CONCLUSION IMPT was associated with less late xerostomia than was IMRT in OPC patients. Oral cavity dosimetric variables were related to the occurrence of late xerostomia.
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16
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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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17
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Arjunan M, Sharma DS, Kaushik S, Krishnan G, Patro KC, Padanthaiyil NM, Rajesh T, Jalali R. A novel hybrid 3D dose reconstruction approach for pre-treatment verification of intensity modulated proton therapy plans. Phys Med Biol 2021; 66:055015. [PMID: 33470967 DOI: 10.1088/1361-6560/abdd8b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
AIM A novel hybrid three-dimensional (3D) dose reconstruction method, based on planar dose measured at a single shallower depth, was developed for use as patient-specific quality assurance (PSQA) of intensity modulated proton therapy (IMPT) plans. The accuracy, robustness and sensitivity of the presented method were validated for multiple IMPT plans of varying complexities. METHODS AND MATERIALS An in-house MATLAB program was developed to reconstruct 3D dose distribution from the planar dose (GyRBE) measured at 3 g cm-2 depth in water or solid phantom using a MatriXX PT ion chamber array. The presented method was validated extensively for 11 single-field optimization (SFO) and multi-field optimization (MFO) plans on Proteus Plus. A total of 47 reconstructed planar doses at different depths were compared against the corresponding RayStation treatment planning system (TPS) and MatriXX PT measurement using a gamma passing rate (γ%) evaluated for 3%/3 mm. The robustness of the reconstruction method with respect to depth, energy layers, field dimensions and complexities in the spot intensity map (SIM) were analysed and compared against the standard PSQA. The sensitivity of the reconstruction method was tested for plans with intentional errors. RESULTS The presented reconstruction method showed excellent agreement (mean γ% > 98%) and robustness with both TPS-calculated and measured dose planes at all depths (2.97-30 g cm-2), energy layers (82.1-225.5 MeV), field dimensions, target volume (17.7-1000 cm3) and SIMs from both SFO and MFO plans. In comparison to the overall mean ± SD γ% from standard PSQA, the reconstruction method showed reductions in mean γ% within 1% for both standard cubes and clinical plans. The reconstruction method was sensitive enough to detect intentional spot positional errors in a selected energy layer of a plan. CONCLUSION The presented hybrid reconstruction method is sufficiently accurate, robust and sensitive to estimate planar dose at any user-defined depth. It simplifies the measurement setup and eliminates multiple depth measurements.
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Affiliation(s)
- Manikandan Arjunan
- Department of Medical Physics, Apollo Proton Cancer Centre, 100 Feet Road Taramani, Chennai, Tamil Nadu, India
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Liu C, Ho MW, Park J, Hsi WC, Liang X, Li Z, Song Y, Feng H, Zhang Y. Fast MCsquare-Based Independent Dose Verification Platform for Pencil Beam Scanning Proton Therapy. Technol Cancer Res Treat 2021; 20:15330338211033076. [PMID: 34338058 PMCID: PMC8326813 DOI: 10.1177/15330338211033076] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 05/17/2021] [Accepted: 06/11/2021] [Indexed: 11/16/2022] Open
Abstract
PURPOSE To commission MCsquare (a multi-cores CPU-based dose calculation engine) for pencil beam scanning (PBS) proton therapy, integrate it into RayStation treatment plan system (TPS) to create a dedicated platform for fast independent dose verification. METHOD A MCsquare-based independent dose verification platform (MC2InRS) was developed to realize automatic dose re-calculation for clinical use, including data preparation, dose calculation, 2D/3D gamma analysis. MCsquare was commissioned based on in-air lateral dose profiles, integrated depth dose, and the absolute dose of different beam energies for Proteus®ONE. MC2InRS was validated with measurement data using various targets and depths in a water phantom. This study also investigated 15 clinical cases to demonstrate the feasibility and effectiveness of MC2InRS platform in clinic practice. RESULTS Between simulation and measurement, the distal range differences at 80% (R80) and 20% (R20) dose levels for each energy were below 0.05 mm, and 0.1 mm, respectively, and the absolute dose differences were below 0.5%. 29 out of 36 QA planes reached a 100% gamma passing rate (GPR) for 2%/2mm criteria, and a minimum of 98.3% gamma was obtained in water phantom between simulation and measurement. For the 15 clinical cases investigated, the average 2D GPR (2%/2mm) was 95.4%, 99.3% for MCsquare vs. measurement, MCsquare vs. TPS, respectively. The average 3D GPR (2%/2mm) was 98.9%, 95.3% for MCsquare vs. TPS in water, and computed tomography (CT), respectively. CONCLUSION MC2InRS, a fast, independent dose verification platform, has been developed to perform dose verification with high accuracy and efficiency for Pencil Bream Scanning (PBS). Its potential to be applied in routine clinical practice has also been discussed.
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Affiliation(s)
- Chunbo Liu
- School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui, China
- University of Florida Health Proton Therapy Institute, Jacksonville, FL, USA
| | - Meng Wei Ho
- University of Florida Health Proton Therapy Institute, Jacksonville, FL, USA
- Department of Radiation Oncology, University of Florida, Gainesville, FL, USA
| | - Jiyeon Park
- University of Florida Health Proton Therapy Institute, Jacksonville, FL, USA
- Department of Radiation Oncology, University of Florida, Gainesville, FL, USA
| | - Wen Chien Hsi
- University of Florida Health Proton Therapy Institute, Jacksonville, FL, USA
- Department of Radiation Oncology, University of Florida, Gainesville, FL, USA
| | - Xiaoying Liang
- University of Florida Health Proton Therapy Institute, Jacksonville, FL, USA
- Department of Radiation Oncology, University of Florida, Gainesville, FL, USA
| | - Zuofeng Li
- University of Florida Health Proton Therapy Institute, Jacksonville, FL, USA
- Department of Radiation Oncology, University of Florida, Gainesville, FL, USA
| | - Yuntao Song
- School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui, China
- Hefei Institute of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, China
| | - Hansheng Feng
- Hefei Institute of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, China
| | - Yawei Zhang
- University of Florida Health Proton Therapy Institute, Jacksonville, FL, USA
- Department of Radiation Oncology, University of Florida, Gainesville, FL, USA
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Maes D, Bowen SR, Regmi R, Bloch C, Wong T, Rosenfeld A, Saini J. A machine learning-based framework for delivery error prediction in proton pencil beam scanning using irradiation log-files. Phys Med 2020; 78:179-186. [PMID: 33038643 DOI: 10.1016/j.ejmp.2020.09.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 09/01/2020] [Accepted: 09/07/2020] [Indexed: 10/23/2022] Open
Abstract
PURPOSE This study aims to investigate the use of machine learning models for delivery error prediction in proton pencil beam scanning (PBS) delivery. METHODS A dataset of planned and delivered PBS spot parameters was generated from a set of 20 prostate patient treatments. Planned spot parameters (spot position, MU and energy) were extracted from the treatment planning system (TPS) for each beam. Delivered spot parameters were extracted from irradiation log-files for each beam delivery following treatment. The dataset was used as a training dataset for three machine learning models which were trained to predict delivered spot parameters based on planned parameters. K-fold cross validation was employed for hyper-parameter tuning and model selection where the mean absolute error (MAE) was used as the model evaluation metric. The model with lowest MAE was then selected to generate a predicted dose distribution for a test prostate patient within a commercial TPS. RESULTS Analysis of the spot position delivery error between planned and delivered values resulted in standard deviations of 0.39 mm and 0.44 mm for x and y spot positions respectively. Prediction error standard deviation values of spot positions using the selected model were 0.22 mm and 0.11 mm for x and y spot positions respectively. Finally, a three-way comparison of dose distributions and DVH values for select OARs indicates that the random-forest-predicted dose distribution within the test prostate patient was in closer agreement to the delivered dose distribution than the planned distribution. CONCLUSIONS PBS delivery error can be accurately predicted using machine learning techniques.
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Affiliation(s)
- Dominic Maes
- Seattle Cancer Care Alliance Proton Therapy Center, 1570 N 115th St., Seattle, WA 98133, USA; Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2500, Australia.
| | - Stephen R Bowen
- Seattle Cancer Care Alliance Proton Therapy Center, 1570 N 115th St., Seattle, WA 98133, USA; Department of Radiation Oncology, University of Washington School of Medicine, 1959 NE Pacific St., Seattle, WA 98195, USA; Department of Radiology, University of Washington School of Medicine, 1959 NE Pacific St., Seattle, WA 98195, USA
| | - Rajesh Regmi
- Seattle Cancer Care Alliance Proton Therapy Center, 1570 N 115th St., Seattle, WA 98133, USA
| | - Charles Bloch
- Seattle Cancer Care Alliance Proton Therapy Center, 1570 N 115th St., Seattle, WA 98133, USA; Department of Radiation Oncology, University of Washington School of Medicine, 1959 NE Pacific St., Seattle, WA 98195, USA
| | - Tony Wong
- Seattle Cancer Care Alliance Proton Therapy Center, 1570 N 115th St., Seattle, WA 98133, USA; Department of Radiation Oncology, University of Washington School of Medicine, 1959 NE Pacific St., Seattle, WA 98195, USA
| | - Anatoly Rosenfeld
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2500, Australia
| | - Jatinder Saini
- Seattle Cancer Care Alliance Proton Therapy Center, 1570 N 115th St., Seattle, WA 98133, USA; Department of Radiation Oncology, University of Washington School of Medicine, 1959 NE Pacific St., Seattle, WA 98195, USA
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20
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Schuy C, Simeonov Y, Durante M, Zink K, Weber U. Technical note: Vendor-agnostic water phantom for 3D dosimetry of complex fields in particle therapy. J Appl Clin Med Phys 2020; 21:227-232. [PMID: 32991056 PMCID: PMC7592961 DOI: 10.1002/acm2.12996] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 06/27/2020] [Accepted: 07/06/2020] [Indexed: 01/08/2023] Open
Abstract
Purpose Three‐dimensional (3D) dosimetry is a necessity to validate patient‐specific treatment plans in particle therapy as well as to facilitate the development of novel treatment modalities. Therefore, a vendor‐agnostic water phantom was developed and verified to measure high resolution 3D dose distributions. Methods The system was experimentally validated at the Marburger Ionenstrahl‐Therapiezentrum using two ionization chamber array detectors (PTW Octavius 1500XDR and 1000P) with 150.68 MeV proton and 285.35 MeV/u 12C beams. The dose distribution of several monoenergetic and complex scanned fields were measured with different step sizes to assess the reproducibility, absolute positioning accuracy, and general performance of the system. Results The developed system was successfully validated and used to automatically measure high resolution 3D dose distributions. The reproducibility in depth was better than ±25 micron. The roll and tilt uncertainty of the detector was estimated to be smaller than ±3 mrad. Conclusions The presented system performed fully automated, high resolution 3D dosimetry, suitable for the validation of complex radiation fields in particle therapy. The measurement quality is comparable to commercially available systems.
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Affiliation(s)
- Christoph Schuy
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Yuri Simeonov
- Institute of Medical Physics and Radiation Protection (IMPS), THM University of Applied Sciences Giessen, Giessen, Germany
| | - Marco Durante
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.,Physics Department, Technische Universität Darmstadt, Darmstadt, Germany
| | - Klemens Zink
- Institute of Medical Physics and Radiation Protection (IMPS), THM University of Applied Sciences Giessen, Giessen, Germany
| | - Uli Weber
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
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21
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Setianegara J, Mazur TR, Maraghechi B, Darafsheh A, Yang D, Zhao T, Li HH. Quantitative proton radiation therapy dosimetry using the storage phosphor europium‐doped potassium chloride. Med Phys 2020; 47:5287-5300. [DOI: 10.1002/mp.14423] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 07/15/2020] [Accepted: 07/21/2020] [Indexed: 11/08/2022] Open
Affiliation(s)
- Jufri Setianegara
- Department of Radiation Oncology Washington University in St. Louis St. Louis MO63110 USA
- Department of Physics Washington University in St. Louis St. Louis MO63110 USA
| | - Thomas R. Mazur
- Department of Radiation Oncology Washington University in St. Louis St. Louis MO63110 USA
| | - Borna Maraghechi
- Department of Radiation Oncology Washington University in St. Louis St. Louis MO63110 USA
| | - Arash Darafsheh
- Department of Radiation Oncology Washington University in St. Louis St. Louis MO63110 USA
| | - Deshan Yang
- Department of Radiation Oncology Washington University in St. Louis St. Louis MO63110 USA
| | - Tianyu Zhao
- Department of Radiation Oncology Washington University in St. Louis St. Louis MO63110 USA
| | - H. Harold Li
- Department of Radiation Oncology Washington University in St. Louis St. Louis MO63110 USA
- Biomedical Engineering Washington University in St. Louis St. Louis MO63110 USA
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22
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Gu W, O'Connor D, Ruan D, Zou W, Dong L, Sheng K. Fraction-variant beam orientation optimization for intensity-modulated proton therapy. Med Phys 2020; 47:3826-3834. [PMID: 32564353 DOI: 10.1002/mp.14340] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 06/03/2020] [Accepted: 06/13/2020] [Indexed: 11/10/2022] Open
Abstract
PURPOSE To achieve a superior balance between dosimetry and the delivery efficiency of intensity-modulated proton therapy (IMPT) using as few beams as possible in a single fraction, we optimally vary beams in different fractions. METHODS In the optimization, 400~800 feasible noncoplanar beams were included in the candidate pool. For each beam, the doses of all scanning spots covering the target volume and a margin were calculated. The fraction-variant beam orientation optimization (FVBOO) problem was formulated to include three terms: two quadratic dose fidelity terms to penalize the deviation of planning target volume fractional dose and organs at risk (OAR) cumulative doses from prescription, respectively; an L2,1/2-norm group sparsity term to control the number of active beams per fraction to between 1 and 4. The Fast Iterative Shrinkage-Thresholding Algorithm (FISTA) was applied to solve this problem. FVBOO was tested on a patient with base-of-skull (BOS) tumor of 5 fractions (5f) and 30 fractions (30f) with an average number of active beams per fraction varying between 4 and 1. In addition, one bilateral head-and-neck (H&N) patient, and one esophageal cancer (ESG) patient of 30f were tested with about three active beams per fraction. The results were compared with IMPT plans that use fixed beams in each fraction. The fixed beams were selected using the group sparsity term with a fraction-invariant BOO (FIBOO) constraint. RESULTS Varying beams were chosen in either the 5f or 30f FVBOO plans. While similar number of beams per fraction was selected as the FIBOO plan, the FVBOO plans were able to spare the OARs better, with an average reduction of [Dmean, Dmax] from the FIBOO plans by [0.85, 2.08] Relative Biological Effective Gy (GyRBE) in the 5f plan and [1.87, 4.06] GyRBE in the 30f plans. While reducing the number of beams per fraction in the BOS patient, a three-beam/fraction 5f FVBOO plan performs comparably as the four-beam FIBOO plan and a two-beam/fraction 30f FVBOO plan still provides superior dosimetry. CONCLUSION Fraction-variant beam orientation optimization allows the utilization of a larger beam solution space for superior dose distribution in IMPT while maintaining a practical number of beams in each fraction.
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Affiliation(s)
- Wenbo Gu
- Department of Radiation Oncology, University of California-Los Angeles, Los Angeles, CA, 90095, USA
| | - Daniel O'Connor
- Department of Radiation Oncology, University of California-Los Angeles, Los Angeles, CA, 90095, USA
| | - Dan Ruan
- Department of Radiation Oncology, University of California-Los Angeles, Los Angeles, CA, 90095, USA
| | - Wei Zou
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Lei Dong
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Ke Sheng
- Department of Radiation Oncology, University of California-Los Angeles, Los Angeles, CA, 90095, USA
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Brodbek L, Kretschmer J, Willborn K, Meijers A, Both S, Langendijk JA, Knopf AC, Looe HK, Poppe B. Analysis of the applicability of two-dimensional detector arrays in terms of sampling rate and detector size to verify scanned intensity-modulated proton therapy plans. Med Phys 2020; 47:4589-4601. [PMID: 32574383 DOI: 10.1002/mp.14346] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 06/10/2020] [Accepted: 06/11/2020] [Indexed: 11/05/2022] Open
Abstract
PURPOSE The introduction of advanced treatment techniques in proton therapy, such as intensity-modulated proton therapy, leads to an increased need for patient-specific quality assurance, especially an accurate treatment plan verification becomes inevitable. In this study, signal theoretical analysis of dose distributions in scanned proton therapy is performed to investigate the feasibility and limits of two-dimensional (2D) detector arrays for treatment plan verification. METHODS 2D detector arrays are characterized by two main aspects: the distance between the single detectors on the array or the sampling frequency; and the lateral response functions of a single detector. The analysis is based on single spots, reference fields and on measured and calculated dose distributions of typical intensity-modulated proton therapy treatment plans with and without range shifter. Measurements were performed with Gafchromic EBT3 films (Ashland Speciality Ingredients G.P., Bridgewater, NJ, USA), the MatriXX PT detector array (IBA Dosimetry, Schwarzenbruck, Germany) and the OCTAVIUS detector array 1500XDR (PTW-Freiburg, Germany) at an IBA Proteus PLUS proton therapy system (Ion Beam Applications, Louvain-la-Neuve, Belgium). Dose calculations were performed with the treatment planning system RayStation 6 or 8 (RaySearch Laboratories, Sweden). RESULTS The Fourier analysis of the data of the treatment planning system and film measurements show maximum frequencies of 0.06/mm for the plan with range shifter and 0.083/mm for the plan without range shifter. According to the Nyquist theorem, this corresponds to minimum required sampling distances of 8.3 and 6 mm, respectively. By comparison, the sampling distances of the arrays of 7.6 mm (MatriXX PT) and 7.1 mm (OD1500XDR) are sufficient to reconstruct the dose distributions adequately from measurements if range shifters are used, whereas some fields of the plans without range shifter violated the Nyquist requirement. The lateral dose response functions of the single detectors within the arrays have clearly higher frequencies than the treatment plans and thus the volume effect only slightly influences the measurements. Consequently, the array measurements show high gamma passing rates with at least 96 % and a good agreement between the investigated line profiles. CONCLUSION The results indicate that the detector dimensions and sampling distances of the arrays are in most studied cases adequate not to substantially influence the measurement process when they are used for analyzing typical intensity-modulated proton therapy treatment plans. Nevertheless, clinical conditions have been identified, for instance treatment plans without range shifter, under which the Nyquist theorem is violated such that a full representation of the dose distributions with the measurements is not feasible. In these cases, analysis of measurements is limited to pointwise comparisons.
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Affiliation(s)
- Leonie Brodbek
- University Clinic for Medical Radiation Physics, Medical Campus Pius Hospital, Carl-von-Ossietzky University, Oldenburg, Germany.,Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Jana Kretschmer
- University Clinic for Medical Radiation Physics, Medical Campus Pius Hospital, Carl-von-Ossietzky University, Oldenburg, Germany
| | - Kay Willborn
- University Clinic for Medical Radiation Physics, Medical Campus Pius Hospital, Carl-von-Ossietzky University, Oldenburg, Germany
| | - Arturs Meijers
- 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
| | - Antje-Christin Knopf
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Hui Khee Looe
- University Clinic for Medical Radiation Physics, Medical Campus Pius Hospital, Carl-von-Ossietzky University, Oldenburg, Germany
| | - Björn Poppe
- University Clinic for Medical Radiation Physics, Medical Campus Pius Hospital, Carl-von-Ossietzky University, Oldenburg, Germany
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Borderías Villarroel E, Geets X, Sterpin E. Online adaptive dose restoration in intensity modulated proton therapy of lung cancer to account for inter-fractional density changes. Phys Imaging Radiat Oncol 2020; 15:30-37. [PMID: 33458323 PMCID: PMC7807540 DOI: 10.1016/j.phro.2020.06.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 06/23/2020] [Accepted: 06/26/2020] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND AND PURPOSE In proton therapy, inter-fractional density changes can severely compromise the effective delivery of the planned dose. Such dose distortion effects can be accounted for by treatment plan adaptation, that requires considerable automation for widespread implementation in clinics. In this study, the clinical benefit of an automatic online adaptive strategy called dose restoration (DR) was investigated. Our objective was to assess to what extent DR could replace the need for a comprehensive offline adaptive strategy. MATERIALS AND METHODS The fully automatic and robust DR workflow was evaluated in a cohort of 14 lung IMPT patients that had a planning-CT and two repeated 4D-CTs (rCT1,rCT2). Initial plans were generated using 4D-robust optimization (including breathing-motion, setup and range errors). DR relied on isodose contours generated from the initial dose and associated patient specific weighted objectives to mimic this initial dose in repeated-CTs. These isodose contours, with their corresponding objectives, were used during re-optimization to compensate proton range distortions disregarding re-contouring. Robustness evaluations were performed for the initial, not-adapted and restored (adapted) plans. RESULTS The resulting DVH-bands showed overall improvement in DVH metrics and robustness levels for restored plans, with respect to not-adapted plans. According to CTV coverage criteria (D95%>95%Dprescription) in not-adapted plans, 35% (5/14) of the cases needed offline adaptation. After DR, Median(D95%) was increased by 1.1 [IQR,0.4] Gy and only one patient out of 14 (7%) still needed offline adaptation because of important anatomical changes. CONCLUSIONS DR has the potential to improve CTV coverage and reduce offline adaptation rate.
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Affiliation(s)
| | - Xavier Geets
- UCLouvain, Molecular Imaging-Radiotherapy and Oncology (MIRO), Brussels, Belgium
- Cliniques Universitaires Saint-Luc, Department of Radiation Oncology, Brussels, Belgium
| | - Edmond Sterpin
- UCLouvain, Molecular Imaging-Radiotherapy and Oncology (MIRO), Brussels, Belgium
- KU Leuven, Department of Oncology, Laboratory of Experimental Radiotherapy, Leuven, Belgium
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Son J, Shin D, Kim T, Park S, Rah JE. Feasibility study of patient-specific energy verification using a multilayer acrylic-disk radiation sensor. Med Phys 2020; 47:3789-3796. [PMID: 32535940 DOI: 10.1002/mp.14326] [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: 01/21/2020] [Revised: 05/14/2020] [Accepted: 06/03/2020] [Indexed: 11/09/2022] Open
Abstract
PURPOSE Obtaining an integral depth-dose (IDD) curve using a recently developed acrylic-disk radiation sensor (ADRS) is time-consuming because its single structure requires point-by-point measurements in a water phantom. The goal of this study was to verify the ability of a newly designed multilayer ADRS, composed of 20 layers, to measure the energy of proton pencil beam scanning (PBS) in patient-specific quality assurance (QA). MATERIALS AND METHODS The multilayer ADRS consisted of a disk-type transmitter, with a diameter of 15 cm and with a thickness of 1 mm, surrounded by a thin optical fiber; this ADRS provided a higher spatial resolution than the single ADRS, which was 2 mm. The dosimetric characteristics of the multilayer ADRS were determined to accurately measure the energy delivered layer-by-layer. We selected five patients to verify the energy measured using the multilayer ADRS from the actual clinical proton therapy plans. The accuracy of the results measured using the multilayer ADRS was compared with that of measurements by a Bragg peak ionization chamber (IC) and that calculated by a Monte Carlo TOPAS simulation. RESULTS The difference between the multilayer ADRS measurements and those of the TOPAS simulation was within 1% for all patients. The ranges, corresponding to the beam energies for each patient, measured using the multilayer ADRS were closer to those calculated using the TOPAS simulation than those measured using the Bragg peak IC. CONCLUSIONS The multilayer ADRS is well suited to verifying the energy of a pencil beam. The acrylic materials used in its configuration make this device easier to use and more cost-effective than conventional detectors. This device, with its high extensibility and stability, may be applicable as a new dosimetry tool for PBS.
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Affiliation(s)
- Jaeman Son
- SNUH Heavy Ion Medical Accelerator of Gijang, Department of Radiation Oncology, Seoul National University Hospital, Seoul, 03080, Korea
| | - Dongho Shin
- Proton Therapy Center, National Cancer Center, Goyang, 10408, Korea
| | - Taeho Kim
- Proton Therapy Center, National Cancer Center, Goyang, 10408, Korea
| | - Sukwon Park
- Department of Radiation Oncology, Myongji Hospital, Hanyang University College of Medicine, Goyang, 10475, Korea
| | - Jeong-Eun Rah
- Department of Radiation Oncology, Myongji Hospital, Hanyang University College of Medicine, Goyang, 10475, Korea
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Albertini F, Matter M, Nenoff L, Zhang Y, Lomax A. Online daily adaptive proton therapy. Br J Radiol 2020; 93:20190594. [PMID: 31647313 PMCID: PMC7066958 DOI: 10.1259/bjr.20190594] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 10/15/2019] [Accepted: 10/22/2019] [Indexed: 12/11/2022] Open
Abstract
It is recognized that the use of a single plan calculated on an image acquired some time before the treatment is generally insufficient to accurately represent the daily dose to the target and to the organs at risk. This is particularly true for protons, due to the physical finite range. Although this characteristic enables the generation of steep dose gradients, which is essential for highly conformal radiotherapy, it also tightens the dependency of the delivered dose to the range accuracy. In particular, the use of an outdated patient anatomy is one of the most significant sources of range inaccuracy, thus affecting the quality of the planned dose distribution. A plan should be ideally adapted as soon as anatomical variations occur, ideally online. In this review, we describe in detail the different steps of the adaptive workflow and discuss the challenges and corresponding state-of-the art developments in particular for an online adaptive strategy.
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Affiliation(s)
| | | | | | - Ye Zhang
- Paul Scherrer Institute, Center for Proton Therapy, Switzerland
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27
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Platform for automatic patient quality assurance via Monte Carlo simulations in proton therapy. Phys Med 2020; 70:49-57. [PMID: 31968277 DOI: 10.1016/j.ejmp.2019.12.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 11/21/2019] [Accepted: 12/18/2019] [Indexed: 12/31/2022] Open
Abstract
For radiation therapy, it is crucial to ensure that the delivered dose matches the planned dose. Errors in the dose calculations done in the treatment planning system (TPS), treatment delivery errors, other software bugs or data corruption during transfer might lead to significant differences between predicted and delivered doses. As such, patient specific quality assurance (QA) of dose distributions, through experimental validation of individual fields, is necessary. These measurement based approaches, however, are performed with 2D detectors, with limited resolution and in a water phantom. Moreover, they are work intensive and often impose a bottleneck to treatment efficiency. In this work, we investigated the potential to replace measurement-based approach with a simulation-based patient specific QA using a Monte Carlo (MC) code as independent dose calculation engine in combination with treatment log files. Our developed QA platform is composed of a web interface, servers and computation scripts, and is capable to autonomously launch simulations, identify and report dosimetric inconsistencies. To validate the beam model of independent MC engine, in-water simulations of mono-energetic layers and 30 SOBP-type dose distributions were performed. Average Gamma passing ratio 99 ± 0.5% for criteria 2%/2 mm was observed. To demonstrate feasibility of the proposed approach, 10 clinical cases such as head and neck, intracranial indications and craniospinal axis, were retrospectively evaluated via the QA platform. The results obtained via QA platform were compared to QA results obtained by measurement-based approach. This comparison demonstrated consistency between the methods, while the proposed approach significantly reduced in-room time required for QA procedures.
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Chen M, Yepes P, Hojo Y, Poenisch F, Li Y, Chen J, Xu C, He X, Gunn GB, Frank SJ, Sahoo N, Li H, Zhu XR, Zhang X. Transitioning from measurement-based to combined patient-specific quality assurance for intensity-modulated proton therapy. Br J Radiol 2019; 93:20190669. [PMID: 31799859 DOI: 10.1259/bjr.20190669] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE This study is part of ongoing efforts aiming to transit from measurement-based to combined patient-specific quality assurance (PSQA) in intensity-modulated proton therapy (IMPT). A Monte Carlo (MC) dose-calculation algorithm is used to improve the independent dose calculation and to reveal the beam modeling deficiency of the analytical pencil beam (PB) algorithm. METHODS A set of representative clinical IMPT plans with suboptimal PSQA results were reviewed. Verification plans were recalculated using an MC algorithm developed in-house. Agreements of PB and MC calculations with measurements that quantified by the γ passing rate were compared. RESULTS The percentage of dose planes that met the clinical criteria for PSQA (>90% γ passing rate using 3%/3 mm criteria) increased from 71.40% in the original PB calculation to 95.14% in the MC recalculation. For fields without beam modifiers, nearly 100% of the dose planes exceeded the 95% γ passing rate threshold using the MC algorithm. The model deficiencies of the PB algorithm were found in the proximal and distal regions of the SOBP, where MC recalculation improved the γ passing rate by 11.27% (p < 0.001) and 16.80% (p < 0.001), respectively. CONCLUSIONS The MC algorithm substantially improved the γ passing rate for IMPT PSQA. Improved modeling of beam modifiers would enable the use of the MC algorithm for independent dose calculation, completely replacing additional depth measurements in IMPT PSQA program. For current users of the PB algorithm, further improving the long-tail modeling or using MC simulation to generate the dose correction factor is necessary. ADVANCES IN KNOWLEDGE We justified a change in clinical practice to achieve efficient combined PSQA in IMPT by using the MC algorithm that was experimentally validated in almost all the clinical scenarios in our center. Deficiencies in beam modeling of the current PB algorithm were identified and solutions to improve its dose-calculation accuracy were provided.
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Affiliation(s)
- Mei Chen
- Department of Radiation Oncology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Pablo Yepes
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.,Physics and Astronomy Department, Rice University, Houston, Texas, USA
| | - Yoshifumi Hojo
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Falk Poenisch
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Yupeng Li
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Jiayi Chen
- Department of Radiation Oncology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Cheng Xu
- Department of Radiation Oncology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiaodong He
- Department of Radiation Oncology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - G Brandon Gunn
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Steven J Frank
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Narayan Sahoo
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Heng Li
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Xiaorong Ronald Zhu
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Xiaodong Zhang
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
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Toscano S, Souris K, Gomà C, Barragán-Montero A, Puydupin S, Stappen FV, Janssens G, Matic A, Geets X, Sterpin E. Impact of machine log-files uncertainties on the quality assurance of proton pencil beam scanning treatment delivery. Phys Med Biol 2019; 64:095021. [PMID: 30897559 DOI: 10.1088/1361-6560/ab120c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Irradiation log-files store useful information about the plan delivery, and together with independent Monte Carlo dose engine calculations can be used to reduce the time needed for patient-specific quality assurance (PSQA). Nonetheless, machine log-files carry an uncertainty associated to the measurement of the spot position and intensity that can influence the correct evaluation of the quality of the treatment delivery. This work addresses the problem of the inclusion of these uncertainties for the final verification of the treatment delivery. Dedicated measurements performed in an IBA Proteus Plus gantry with a pencil beam scanning (PBS) dedicated nozzle have been carried out to build a 'room-dependent' model of the spot position uncertainties. The model has been obtained through interpolation of the look-up tables describing the systematic and random uncertainties, and it has been tested for a clinical case of a brain cancer patient irradiated in a dry-run. The delivered dose has been compared with the planned dose with the inclusion of the errors obtained applying the model. Our results suggest that the accuracy of the treatment delivery is higher than the spot position uncertainties obtained from the log-file records. The comparison in terms of DVHs shows that the log-reconstructed dose is compatible with the planned dose within the 95% confidence interval obtained applying our model. The initial mean dose difference between the calculated dose to the patient based on the plan and recorded data is around 1%. The difference is essentially due to the log-file uncertainties and it can be removed with a correct treatment of these errors. In conclusion our new PSQA protocol allows for a fast verification of the dose delivered after every treatment fraction through the use of machine log-files and an independent Monte Carlo dose engine. Moreover, the inclusion of log-file uncertainties in the dose calculation allows for a correct evaluation of the quality of the treatment plan delivery.
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Affiliation(s)
- S Toscano
- Laboratory of Experimental Radiotherapy, Department of Oncology, KU Leuven, Leuven, Belgium. Current address: Université Libre de Bruxelles, Avenue Franklin Roosevelt 50, 1050 Bruxelles, Belgium. Author to whom any correspondence should be addressed
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Johnson JE, Beltran C, Wan Chan Tseung H, Mundy DW, Kruse JJ, Whitaker TJ, Herman MG, Furutani KM. Highly efficient and sensitive patient-specific quality assurance for spot-scanned proton therapy. PLoS One 2019; 14:e0212412. [PMID: 30763390 PMCID: PMC6375645 DOI: 10.1371/journal.pone.0212412] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 02/02/2019] [Indexed: 12/02/2022] Open
Abstract
The purpose of this work was to develop an end-to-end patient-specific quality assurance (QA) technique for spot-scanned proton therapy that is more sensitive and efficient than traditional approaches. The patient-specific methodology relies on independently verifying the accuracy of the delivered proton fluence and the dose calculation in the heterogeneous patient volume. A Monte Carlo dose calculation engine, which was developed in-house, recalculates a planned dose distribution on the patient CT data set to verify the dose distribution represented by the treatment planning system. The plan is then delivered in a pre-treatment setting and logs of spot position and dose monitors, which are integrated into the treatment nozzle, are recorded. A computational routine compares the delivery log to the DICOM spot map used by the Monte Carlo calculation to ensure that the delivered parameters at the machine match the calculated plan. Measurements of dose planes using independent detector arrays, which historically are the standard approach to patient-specific QA, are not performed for every patient. The nozzle-integrated detectors are rigorously validated using independent detectors in regular QA intervals. The measured data are compared to the expected delivery patterns. The dose monitor reading deviations are reported in a histogram, while the spot position discrepancies are plotted vs. spot number to facilitate independent analysis of both random and systematic deviations. Action thresholds are linked to accuracy of the commissioned delivery system. Even when plan delivery is acceptable, the Monte Carlo second check system has identified dose calculation issues which would not have been illuminated using traditional, phantom-based measurement techniques. The efficiency and sensitivity of our patient-specific QA program has been improved by implementing a procedure which independently verifies patient dose calculation accuracy and plan delivery fidelity. Such an approach to QA requires holistic integration and maintenance of patient-specific and patient-independent QA.
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Affiliation(s)
- J. E. Johnson
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - C. Beltran
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - H. Wan Chan Tseung
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - D. W. Mundy
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - J. J. Kruse
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - T. J. Whitaker
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - M. G. Herman
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - K. M. Furutani
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, United States of America
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Winterhalter C, Meier G, Oxley D, Weber DC, Lomax AJ, Safai S. Log file based Monte Carlo calculations for proton pencil beam scanning therapy. Phys Med Biol 2019; 64:035014. [PMID: 30540984 DOI: 10.1088/1361-6560/aaf82d] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Patient specific quality assurance is crucial to guarantee safety in proton pencil beam scanning. In current clinical practice, this requires extensive, time consuming measurements. Additionally, these measurements do not consider the influence of density heterogeneities in the patient and are insensitive to delivery errors. In this work, we investigate the use of log file based Monte Carlo calculations for dose reconstructions in the patient CT, which takes the combined influence of calculational and delivery errors into account. For one example field, 87%/90% of the voxels agree within ±3% when taking either calculational or delivery uncertainties into account (analytical versus Monte Carlo calculation/Monte Carlo from planned versus Monte Carlo from log file). 78% agree when considering both uncertainties simultaneously (nominal field versus Monte Carlo from log files). We then show the application of the log file based Monte Carlo calculations as a patient specific quality assurance tool for a set of five patients (16 fields) treated for different indications. For all fields, absolute dose scaling factors based on the log file Monte Carlo agree within ±3% to the measurement based absolute dose scaling. Relative comparison shows that more than 90% of the voxels agree within ± 5% between the analytical calculated plan and the Monte Carlo based on log files. The log file based Monte Carlo approach is an end-to-end test incorporating all requirements of patient specific quality assurance. It has the potential to reduce the workload and therefore to increase the patient throughput, while simultaneously enabling more accurate dose verification directly in the patient geometry.
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Affiliation(s)
- Carla Winterhalter
- Centre for Proton Therapy, Paul Scherrer Institute, Villigen, Switzerland. Department of Physics, ETH Zurich, Zurich, Switzerland
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Yasui K, Toshito T, Omachi C, Hayashi K, Kinou H, Katsurada M, Hayashi N, Ogino H. Dosimetric verification of IMPT using a commercial heterogeneous phantom. J Appl Clin Med Phys 2019; 20:114-120. [PMID: 30673145 PMCID: PMC6371016 DOI: 10.1002/acm2.12535] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 11/19/2018] [Accepted: 12/30/2018] [Indexed: 11/13/2022] Open
Abstract
The purpose of this study was to propose a verification method and results of intensity‐modulated proton therapy (IMPT), using a commercially available heterogeneous phantom. We used a simple simulated head and neck and prostate phantom. An ionization chamber and radiochromic film were used for measurements of absolute dose and relative dose distribution. The measured doses were compared with calculated doses using a treatment planning system. We defined the uncertainty of the measurement point of the ionization chamber due to the effective point of the chamber and mechanical setup error as 2 mm and estimated the dose variation base on a 2 mm error. We prepared a HU‐relative stopping power conversion table and fluence correction factor that were specific to the heterogeneous phantom. The fluence correction factor was determined as a function of depth and was obtained from the ratio of the doses in water and in the phantom at the same effective depths. In the simulated prostate plan, composite doses of measurements and calculations agreed within ±1.3% and the maximum local dose differences of each field were 10.0%. Composite doses in the simulated head and neck plan agreed within 4.0% and the maximum local dose difference for each field was 12.0%. The dose difference for each field came within 2% when taking the measurement uncertainty into consideration. In the composite plan, the maximum dose uncertainty was estimated as 4.0% in the simulated prostate plan and 5.8% in the simulated head and neck plan. Film measurements showed good agreement, with more than 92.5% of points passing a gamma value (3%/3 mm). From these results, the heterogeneous phantom should be useful for verification of IMPT by using a phantom‐specific HU‐relative stopping power conversion, fluence correction factor, and dose error estimation due to the effective point of the chamber.
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Affiliation(s)
- Keisuke Yasui
- Faculty of Radiological Technology, School of Health Sciences, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan
| | - Toshiyuki Toshito
- Nagoya Proton Therapy Center, Nagoya City West Medical Center, 1-1-1, Hirate-cho, Kita-ku, Nagoya, Aichi, 462-8508, Japan
| | - Chihiro Omachi
- Nagoya Proton Therapy Center, Nagoya City West Medical Center, 1-1-1, Hirate-cho, Kita-ku, Nagoya, Aichi, 462-8508, Japan
| | - Kensuke Hayashi
- Nagoya Proton Therapy Center, Nagoya City West Medical Center, 1-1-1, Hirate-cho, Kita-ku, Nagoya, Aichi, 462-8508, Japan
| | - Hideto Kinou
- Nagoya Proton Therapy Center, Nagoya City West Medical Center, 1-1-1, Hirate-cho, Kita-ku, Nagoya, Aichi, 462-8508, Japan
| | - Masaki Katsurada
- Nagoya Proton Therapy Center, Nagoya City West Medical Center, 1-1-1, Hirate-cho, Kita-ku, Nagoya, Aichi, 462-8508, Japan
| | - Naoki Hayashi
- Faculty of Radiological Technology, School of Health Sciences, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan
| | - Hiroyuki Ogino
- Nagoya Proton Therapy Center, Nagoya City West Medical Center, 1-1-1, Hirate-cho, Kita-ku, Nagoya, Aichi, 462-8508, Japan
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Intensity modulated proton therapy (IMPT) - The future of IMRT for head and neck cancer. Oral Oncol 2018; 88:66-74. [PMID: 30616799 DOI: 10.1016/j.oraloncology.2018.11.015] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 11/11/2018] [Accepted: 11/12/2018] [Indexed: 12/13/2022]
Abstract
Radiation therapy plays an integral role in the management of head and neck cancers (HNCs). While most HNC patients have historically been treated with photon-based radiation techniques such as intensity modulated radiation therapy (IMRT), there is a growing awareness of the potential clinical benefits of proton therapy over IMRT in the definitive, postoperative and reirradiation settings given the unique physical properties of protons. Intensity modulated proton therapy (IMPT), also known as "pencil beam proton therapy," is a sophisticated mode of proton therapy that is analogous to IMRT and an active area of investigation in cancer care. Multifield optimization IMPT allows for high quality plans that can target superficially located HNCs as well as large neck volumes while significantly reducing integral doses. Several dosimetric studies have demonstrated the superiority of IMPT over IMRT to improve dose sparing of nearby organs such as the larynx, salivary glands, and esophagus. Evidence of the clinical translation of these dosimetric advantages has been demonstrated with documented toxicity reductions (such as decreased feeding tube dependency) after IMPT for patients with HNCs. While there are relative challenges to IMPT planning that exist today such as particle range uncertainties and high sensitivity to anatomical changes, ongoing investigations in image-guidance techniques and robust optimization methods are promising. A systematic approach towards utilizing IMPT and additional prospective studies are necessary in order to more accurately estimate the clinical benefit of IMPT over IMRT and passive proton therapy on a case-by-case basis for patients with sub-site specific HNCs.
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Hernandez Morales D, Shan J, Liu W, Augustine KE, Bues M, Davis MJ, Fatyga M, Johnson JE, Mundy DW, Shen J, Younkin JE, Stoker JB. Automation of routine elements for spot-scanning proton patient-specific quality assurance. Med Phys 2018; 46:5-14. [PMID: 30339270 DOI: 10.1002/mp.13246] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Revised: 09/12/2018] [Accepted: 10/07/2018] [Indexed: 11/11/2022] Open
Abstract
PURPOSE At our institution, all proton patient plans undergo patient-specific quality assurance (PSQA) prior to treatment delivery. For intensity-modulated proton beam therapy, quality assurance is complex and time consuming, and it may involve multiple measurements per field. We reviewed our PSQA workflow and identified the steps that could be automated and developed solutions to improve efficiency. METHODS We used the treatment planning system's (TPS) capability to support C# scripts to develop an Eclipse scripting application programming interface (ESAPI) script and automate the preparation of the verification phantom plan for measurements. A local area network (LAN) connection between our measurement equipment and shared database was established to facilitate equipment control, measurement data transfer, and storage. To improve the analysis of the measurement data, a Python script was developed to automatically perform a 2D-3D γ-index analysis comparing measurements in the plane of a two-dimensional detector array with TPS predictions in a water phantom for each acquired measurement. RESULTS Device connection via LAN granted immediate access to the plan and measurement information for downstream analysis using an online software suite. Automated scripts applied to verification plans reduced time from preparation steps by at least 50%; time reduction from automating γ-index analysis was even more pronounced, dropping by a factor of 10. On average, we observed an overall time savings of 55% in completion of the PSQA per patient plan. CONCLUSIONS The automation of the routine tasks in the PSQA workflow significantly reduced the time required per patient, reduced user fatigue, and frees up system users from routine and repetitive workflow steps allowing increased focus on evaluating key quality metrics.
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Affiliation(s)
| | - Jie Shan
- Biomedical Informatics Department, Arizona State University, Scottsdale, AZ, 85259, USA
| | - Wei Liu
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - Kurt E Augustine
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - Martin Bues
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - Michael J Davis
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - Mirek Fatyga
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - Jedediah E Johnson
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Daniel W Mundy
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Jiajian Shen
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - James E Younkin
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
| | - Joshua B Stoker
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ, 85054, USA
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Matter M, Nenoff L, Meier G, Weber DC, Lomax AJ, Albertini F. Alternatives to patient specific verification measurements in proton therapy: a comparative experimental study with intentional errors. ACTA ACUST UNITED AC 2018; 63:205014. [DOI: 10.1088/1361-6560/aae2f4] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Trnková P, Knäusl B, Actis O, Bert C, Biegun AK, Boehlen TT, Furtado H, McClelland J, Mori S, Rinaldi I, Rucinski A, Knopf AC. Clinical implementations of 4D pencil beam scanned particle therapy: Report on the 4D treatment planning workshop 2016 and 2017. Phys Med 2018; 54:121-130. [PMID: 30337001 DOI: 10.1016/j.ejmp.2018.10.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 09/18/2018] [Accepted: 10/02/2018] [Indexed: 12/14/2022] Open
Abstract
In 2016 and 2017, the 8th and 9th 4D treatment planning workshop took place in Groningen (the Netherlands) and Vienna (Austria), respectively. This annual workshop brings together international experts to discuss research, advances in clinical implementation as well as problems and challenges in 4D treatment planning, mainly in spot scanned proton therapy. In the last two years several aspects like treatment planning, beam delivery, Monte Carlo simulations, motion modeling and monitoring, QA phantoms as well as 4D imaging were thoroughly discussed. This report provides an overview of discussed topics, recent findings and literature review from the last two years. Its main focus is to highlight translation of 4D research into clinical practice and to discuss remaining challenges and pitfalls that still need to be addressed and to be overcome.
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Affiliation(s)
- Petra Trnková
- HollandPTC, P.O. Box 5046, 2600 GA Delft, the Netherlands; Erasmus MC, P.O. Box 5201, 3008 AE Rotterdam, the Netherlands
| | - Barbara Knäusl
- Department of Radiation Oncology, Division of Medical Radiation Physics, Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna/AKH Vienna, Austria
| | - Oxana Actis
- Paul Scherrer Institute (PSI), 5232 Villigen, Switzerland
| | - Christoph Bert
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany
| | - Aleksandra K Biegun
- KVI-Center for Advanced Radiation Technology, University of Groningen, Groningen, the Netherlands
| | - Till T Boehlen
- Paul Scherrer Institute (PSI), 5232 Villigen, Switzerland
| | - Hugo Furtado
- Department of Radiation Oncology, Division of Medical Radiation Physics, Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna/AKH Vienna, Austria
| | - Jamie McClelland
- Centre for Medical Image Computing, Dept. Medical Physics and Biomedical, University College London, London, UK
| | - Shinichiro Mori
- National Institute of Radiological Sciences for Charged Particle Therapy, Chiba, Japan
| | - Ilaria Rinaldi
- Lyon 1 University and CNRS/IN2P3, UMR 5822, 69622 Villeurbanne, France; MAASTRO Clinic, P.O. Box 3035, 6202 NA Maastricht, the Netherlands
| | | | - Antje C Knopf
- University of Groningen, University Medical Center Groningen, Department of Radiation Oncology, Groningen, the Netherlands.
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Blanchard P, Gunn GB, Lin A, Foote RL, Lee NY, Frank SJ. Proton Therapy for Head and Neck Cancers. Semin Radiat Oncol 2018; 28:53-63. [PMID: 29173756 DOI: 10.1016/j.semradonc.2017.08.004] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Because of its sharp lateral penumbra and steep distal fall-off, proton therapy offers dosimetric advantages over photon therapy. In head and neck cancer, proton therapy has been used for decades in the treatment of skull-base tumors. In recent years the use of proton therapy has been extended to numerous other disease sites, including nasopharynx, oropharynx, nasal cavity and paranasal sinuses, periorbital tumors, skin, and salivary gland, or to reirradiation. The aim of this review is to present the physical properties and dosimetric benefit of proton therapy over advanced photon therapy; to summarize the clinical benefit described for each disease site; and to discuss issues of patient selection and cost-effectiveness.
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Affiliation(s)
- Pierre Blanchard
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX; Department of Radiation Oncology, Institut Gustave Roussy, Villejuif, France
| | - Gary Brandon Gunn
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - Alexander Lin
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA
| | - Robert L Foote
- Departments of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - Nancy Y Lee
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Steven J Frank
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX.
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Bernatowicz K, Geets X, Barragan A, Janssens G, Souris K, Sterpin E. Feasibility of online IMPT adaptation using fast, automatic and robust dose restoration. Phys Med Biol 2018; 63:085018. [PMID: 29595145 DOI: 10.1088/1361-6560/aaba8c] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Intensity-modulated proton therapy (IMPT) offers excellent dose conformity and healthy tissue sparing, but it can be substantially compromised in the presence of anatomical changes. A major dosimetric effect is caused by density changes, which alter the planned proton range in the patient. Three different methods, which automatically restore an IMPT plan dose on a daily CT image were implemented and compared: (1) simple dose restoration (DR) using optimization objectives of the initial plan, (2) voxel-wise dose restoration (vDR), and (3) isodose volume dose restoration (iDR). Dose restorations were calculated for three different clinical cases, selected to test different capabilities of the restoration methods: large range adaptation, complex dose distributions and robust re-optimization. All dose restorations were obtained in less than 5 min, without manual adjustments of the optimization settings. The evaluation of initial plans on repeated CTs showed large dose distortions, which were substantially reduced after restoration. In general, all dose restoration methods improved DVH-based scores in propagated target volumes and OARs. Analysis of local dose differences showed that, although all dose restorations performed similarly in high dose regions, iDR restored the initial dose with higher precision and accuracy in the whole patient anatomy. Median dose errors decreased from 13.55 Gy in distorted plan to 9.75 Gy (vDR), 6.2 Gy (DR) and 4.3 Gy (iDR). High quality dose restoration is essential to minimize or eventually by-pass the physician approval of the restored plan, as long as dose stability can be assumed. Motion (as well as setup and range uncertainties) can be taken into account by including robust optimization in the dose restoration. Restoring clinically-approved dose distribution on repeated CTs does not require new ROI segmentation and is compatible with an online adaptive workflow.
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Affiliation(s)
- Kinga Bernatowicz
- Université catholique de Louvain, Center of Molecular Imaging, Radiotherapy and Oncology, Brussels, Belgium
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Giordanengo S, Manganaro L, Vignati A. Review of technologies and procedures of clinical dosimetry for scanned ion beam radiotherapy. Phys Med 2017; 43:79-99. [DOI: 10.1016/j.ejmp.2017.10.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 09/23/2017] [Accepted: 10/18/2017] [Indexed: 12/17/2022] Open
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Tran LT, Chartier L, Bolst D, Pogossov A, Guatelli S, Petasecca M, Lerch MLF, Prokopovich DA, Reinhard MI, Clasie B, Depauw N, Kooy H, Flanz JB, McNamara A, Paganetti H, Beltran C, Furutani K, Perevertaylo VL, Jackson M, Rosenfeld AB. Characterization of proton pencil beam scanning and passive beam using a high spatial resolution solid‐state microdosimeter. Med Phys 2017; 44:6085-6095. [DOI: 10.1002/mp.12563] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 07/31/2017] [Accepted: 08/25/2017] [Indexed: 11/08/2022] Open
Affiliation(s)
- Linh T. Tran
- Centre for Medical Radiation Physics University of Wollongong Wollongong Australia
| | - Lachlan Chartier
- Centre for Medical Radiation Physics University of Wollongong Wollongong Australia
| | - David Bolst
- Centre for Medical Radiation Physics University of Wollongong Wollongong Australia
| | - Alex Pogossov
- Centre for Medical Radiation Physics University of Wollongong Wollongong Australia
| | - Susanna Guatelli
- Centre for Medical Radiation Physics University of Wollongong Wollongong Australia
| | - Marco Petasecca
- Centre for Medical Radiation Physics University of Wollongong Wollongong Australia
| | - Michael L. F. Lerch
- Centre for Medical Radiation Physics University of Wollongong Wollongong Australia
| | - Dale A. Prokopovich
- Australian Nuclear Science and Technology Organisation Lucas Heights Australia
| | - Mark I. Reinhard
- Australian Nuclear Science and Technology Organisation Lucas Heights Australia
| | - Benjamin Clasie
- Department of Radiation Oncology Massachusetts General Hospital & Harvard Medical School Boston MA USA
| | - Nicolas Depauw
- Department of Radiation Oncology Massachusetts General Hospital & Harvard Medical School Boston MA USA
| | - Hanne Kooy
- Department of Radiation Oncology Massachusetts General Hospital & Harvard Medical School Boston MA USA
| | - Jacob B. Flanz
- Department of Radiation Oncology Massachusetts General Hospital & Harvard Medical School Boston MA USA
| | - Aimee McNamara
- Department of Radiation Oncology Massachusetts General Hospital & Harvard Medical School Boston MA USA
| | - Harald Paganetti
- Department of Radiation Oncology Massachusetts General Hospital & Harvard Medical School Boston MA USA
| | | | | | | | - Michael Jackson
- Radiation Oncology Department Prince of Wales Hospital Randwick NSW 2031 Australia
| | - Anatoly B. Rosenfeld
- Centre for Medical Radiation Physics University of Wollongong Wollongong Australia
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Consensus Guidelines for Implementing Pencil-Beam Scanning Proton Therapy for Thoracic Malignancies on Behalf of the PTCOG Thoracic and Lymphoma Subcommittee. Int J Radiat Oncol Biol Phys 2017; 99:41-50. [DOI: 10.1016/j.ijrobp.2017.05.014] [Citation(s) in RCA: 145] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 04/05/2017] [Accepted: 05/09/2017] [Indexed: 12/25/2022]
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Blanchard P, Frank SJ. [Proton therapy for head and neck cancers]. Cancer Radiother 2017; 21:515-520. [PMID: 28869195 DOI: 10.1016/j.canrad.2017.06.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 06/27/2017] [Accepted: 06/30/2017] [Indexed: 12/23/2022]
Abstract
The absence of exit dose and the sharp lateral penumbra are key assets for proton therapy, which are responsible for its dosimetric superiority over advanced photon radiotherapy. Dosimetric comparisons have consistently shown a reduction of the integral dose and the dose to organs at risk favouring intensity-modulated proton therapy (IMPT) over intensity-modulated radiotherapy (IMRT). The structures that benefit the most of these dosimetric improvements in head and neck cancers are the anterior oral cavity, the posterior fossa, the visual apparatus and swallowing structures. A number of publications have concluded that these dosimetric differences actually translate into reduced toxicities with IMPT, for example with regards to reduced weight loss or need for feeding tube. Patient survival is usually similar to IMRT series, except in base of skull or sinonasal malignancies, where a survival advantage of IMPT could exist. The goals of the present review is to describe the major characteristics of proton therapy, to analyse the clinical data with regards to head and neck cancer patients, and to highlight the issue of patient selection and physical and biological uncertainties.
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Affiliation(s)
- P Blanchard
- Department of radiation oncology, MD Anderson cancer center, the university of Texas, Houston, Texas, États-Unis; Département de radiothérapie, Gustave-Roussy cancer campus, 114, rue Édouard-Vaillant, 94800 Villejuif, France.
| | - S J Frank
- Department of radiation oncology, MD Anderson cancer center, the university of Texas, Houston, Texas, États-Unis
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43
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Zhang Y, Kerr MD, Guan F, Hartman J, Jiang B, Sahoo N, Zhu XR, Gillin MT, Qian W, Zhang X. Dose calculation for spot scanning proton therapy with the application of a range shifter. Biomed Phys Eng Express 2017. [DOI: 10.1088/2057-1976/aa726a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Trnková P, Bolsi A, Albertini F, Weber DC, Lomax AJ. Factors influencing the performance of patient specific quality assurance for pencil beam scanning IMPT fields. Med Phys 2017; 43:5998. [PMID: 27806620 DOI: 10.1118/1.4964449] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE A detailed analysis of 2728 intensity modulated proton therapy (IMPT) fields that were clinically delivered to patients between 2007 and 2013 at Paul Scherrer Institute (PSI) was performed. The aim of this study was to analyze the results of patient specific dosimetric verifications and to assess possible correlation between the quality assurance (QA) results and specific field metrics. METHODS Dosimetric verifications were performed for every IMPT field prior to patient treatment. For every field, a steering file was generated containing all the treatment unit information necessary for treatment delivery: beam energy, beam angle, dose, size of air gap, nuclear interaction (NI) correction factor, number of range shifter plates, number of Bragg peaks (BPs) with their position and weight. This information was extracted and correlated to the results of dosimetric verification of each field which was a measurement of two orthogonal profiles using an orthogonal ionization chamber array in a movable water column. RESULTS The data analysis has shown more than 94% of all verified plans were within defined clinical tolerances. The differences between measured and calculated dose depend critically on the number of BPs, total thickness of all range shifter plates inserted in the beam path, and maximal range. An increase of the dose difference was observed with smaller number of BPs (i.e., smaller tumor) and smaller ranges (i.e., superficial tumors). The results of the verification do not depend, however, on the prescribed dose, NI correction, or the size of the air gap. There is no dependency of the transversal and longitudinal spot position precision on the beam angle. The value of NI correction depends on the number of spots and number of range shifter plates. CONCLUSIONS The presented study has shown that the verification method used at Centre for Proton Therapy at Paul Scherrer Institute is accurate and reproducible for performing patient specific QA. The results confirmed that the dose discrepancy is dependent on the size and location of the tumor.
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Affiliation(s)
- P Trnková
- Centre for Proton Therapy, Paul Scherrer Institute, PSI West, Villigen 5232, Switzerland
| | - A Bolsi
- Centre for Proton Therapy, Paul Scherrer Institute, PSI West, Villigen 5232, Switzerland
| | - F Albertini
- Centre for Proton Therapy, Paul Scherrer Institute, PSI West, Villigen 5232, Switzerland
| | - D C Weber
- Centre for Proton Therapy, Paul Scherrer Institute, PSI West, Villigen 5232, Switzerland and Radiation Oncology Department, University of Zürich, Rämistrasse 71, Zürich 8006, Switzerland
| | - A J Lomax
- Centre for Proton Therapy, Paul Scherrer Institute, PSI West, Villigen 5232, Switzerland and Department of Physics, ETH Zürich, Rämistrasse 101, Zürich 8092, Switzerland
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45
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Batista V, Chaudhri N, Richter D, Herfarth K, Jäkel O. Internal target volume margins for liver tumours treated with gated scanned carbon-ion radiotherapy. Biomed Phys Eng Express 2017. [DOI: 10.1088/2057-1976/aa5988] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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46
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Lin Y, Clasie B, Lu HM, Flanz J, Shen T, Jee KW. Impacts of gantry angle dependent scanning beam properties on proton PBS treatment. Phys Med Biol 2016; 62:344-357. [DOI: 10.1088/1361-6560/aa5084] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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47
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Blanchard P, Wong AJ, Gunn GB, Garden AS, Mohamed ASR, Rosenthal DI, Crutison J, Wu R, Zhang X, Zhu XR, Mohan R, Amin MV, Fuller CD, Frank SJ. Toward a model-based patient selection strategy for proton therapy: External validation of photon-derived normal tissue complication probability models in a head and neck proton therapy cohort. Radiother Oncol 2016; 121:381-386. [PMID: 27641784 PMCID: PMC5474306 DOI: 10.1016/j.radonc.2016.08.022] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 08/17/2016] [Accepted: 08/29/2016] [Indexed: 02/06/2023]
Abstract
OBJECTIVE To externally validate head and neck cancer (HNC) photon-derived normal tissue complication probability (NTCP) models in patients treated with proton beam therapy (PBT). METHODS This prospective cohort consisted of HNC patients treated with PBT at a single institution. NTCP models were selected based on the availability of data for validation and evaluated by using the leave-one-out cross-validated area under the curve (AUC) for the receiver operating characteristics curve. RESULTS 192 patients were included. The most prevalent tumor site was oropharynx (n=86, 45%), followed by sinonasal (n=28), nasopharyngeal (n=27) or parotid (n=27) tumors. Apart from the prediction of acute mucositis (reduction of AUC of 0.17), the models overall performed well. The validation (PBT) AUC and the published AUC were respectively 0.90 versus 0.88 for feeding tube 6months PBT; 0.70 versus 0.80 for physician-rated dysphagia 6months after PBT; 0.70 versus 0.68 for dry mouth 6months after PBT; and 0.73 versus 0.85 for hypothyroidism 12months after PBT. CONCLUSION Although a drop in NTCP model performance was expected for PBT patients, the models showed robustness and remained valid. Further work is warranted, but these results support the validity of the model-based approach for selecting treatment for patients with HNC.
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Affiliation(s)
- Pierre Blanchard
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA; Department of Radiation Oncology, Gustave Roussy Cancer Campus, Villejuif, France
| | - Andrew J Wong
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - G Brandon Gunn
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Adam S Garden
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Abdallah S R Mohamed
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - David I Rosenthal
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Joseph Crutison
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Richard Wu
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Xiaodong Zhang
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - X Ronald Zhu
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Radhe Mohan
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Mayankkumar V Amin
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - C David Fuller
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Steven J Frank
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA.
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[Technical aspects of protontherapy: Setup, equipment and radioprotection]. Cancer Radiother 2016; 20:519-22. [PMID: 27614510 DOI: 10.1016/j.canrad.2016.07.091] [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: 07/29/2016] [Accepted: 07/29/2016] [Indexed: 11/21/2022]
Abstract
The number of protontherapy facilities is still increasing rapidly with more than 30 ongoing projects and close to 60 currently under operation. Although the technology is now validated and robust, a proton facility cannot be considered as a standard radiation therapy equipment: its constraints in terms of building, services, project management are of paramount impact at the level of the hospital. Therefore, a protontherapy project must be carefully considered and prepared, which is mandatory for further fluid and efficient clinical operation.
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Pugh TJ, Choi S, Nogueras-Gonzalaez GM, Nguyen QN, Mahmood U, Frank SJ, Mathai B, Zhu XR, Sahoo N, Gillin M, Kuban DA, Hoffman KE, McGuire SE, Lee AK. Proton Beam Therapy for Localized Prostate Cancer: Results from a Prospective Quality-of-Life Trial. Int J Part Ther 2016; 3:27-36. [PMID: 31772973 DOI: 10.14338/ijpt-16-00006.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Accepted: 06/06/2016] [Indexed: 11/21/2022] Open
Abstract
Purpose To report prostate cancer outcomes, toxicity, and quality of life (QOL) in men treated with proton beam therapy (PBT). Patients and Methods Patients were enrolled in a prospective trial. All participants received 75.6 to 78 Gy (RBE). Up to 6 months of luteinizing hormone-releasing hormone agonist therapy was allowed. The Phoenix definition defined biochemical failure. Modified Radiation Therapy Oncology Group criteria defined toxicity. Expanded Prostate Cancer Index Composite questionnaires objectified QOL. Clinically significant QOL decrement was defined as ≥0.5 × baseline standard deviation. Results In total, 423 men were analyzed. The National Comprehensive Cancer Network risk classification was used (low 43%; intermediate 56%; high 1%). At the 5.2-year median follow-up, overall and disease-specific survival rates were 99.8% and 100%, respectively. Cumulative biochemical failure rate was 5.2% (95% confidence interval [CI] = 3.0%-8.3%); acute grade 2 genitourinary (GU) toxicity was 46.3%; acute grade 2 gastrointestinal (GI) toxicity was 5.0% (95% CI = 3.1%-7.3%). There was no acute grade ≥3 GI or GU toxicity. Cumulative late grade 2 GU and GI toxicity was 15.9% (95% CI = 13%-20%) and 9.7% (95% CI = 6.5%-12%), respectively. There were 2 grade 3 late GI toxicities (rectal bleeding) and no late grade ≥3 GU toxicity. The 4-year mean Expanded Prostate Cancer Index Composite urinary, bowel, sexual, and hormonal summary scores (range; standard deviation) were 89.7 (43.8-100; 11), 91.3 (41.1-94.6; 10), 57.8 (0.0-96.2; 27.1), and 92.2 (25-95.5; 10.5), respectively. Compared with baseline, there was no clinically significant decrement in urinary, sexual, or hormonal QOL after treatment completion. A modest (<10 points), yet clinically significant, decrement in bowel QOL was appreciated throughout follow-up. Conclusion Contemporary PBT resulted in excellent biochemical control, minimal risk of higher-grade toxicity, and modest QOL decrement. Further investigation comparing PBT with alternative prostate cancer treatment strategies are warranted.
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Affiliation(s)
| | - Seungtaek Choi
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | | | - Quyhn Nhu Nguyen
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Usama Mahmood
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Steven J Frank
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Benson Mathai
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - X Ron Zhu
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Narayan Sahoo
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Michael Gillin
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Deborah A Kuban
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Karen E Hoffman
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Sean E McGuire
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Andrew K Lee
- Texas Center for Proton Therapy, Irving, TX, USA
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50
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Blanchard P, Garden AS, Gunn GB, Rosenthal DI, Morrison WH, Hernandez M, Crutison J, Lee JJ, Ye R, Fuller CD, Mohamed ASR, Hutcheson KA, Holliday EB, Thaker NG, Sturgis EM, Kies MS, Zhu XR, Mohan R, Frank SJ. Intensity-modulated proton beam therapy (IMPT) versus intensity-modulated photon therapy (IMRT) for patients with oropharynx cancer - A case matched analysis. Radiother Oncol 2016; 120:48-55. [PMID: 27342249 PMCID: PMC5474304 DOI: 10.1016/j.radonc.2016.05.022] [Citation(s) in RCA: 157] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 05/17/2016] [Accepted: 05/18/2016] [Indexed: 11/16/2022]
Abstract
BACKGROUND Owing to its physical properties, intensity-modulated proton therapy (IMPT) used for patients with oropharyngeal carcinoma has the ability to reduce the dose to organs at risk compared to intensity-modulated radiotherapy (IMRT) while maintaining adequate tumor coverage. Our aim was to compare the clinical outcomes of these two treatment modalities. METHODS We performed a 1:2 matching of IMPT to IMRT patients. Our study cohort consisted of IMPT patients from a prospective quality of life study and consecutive IMRT patients treated at a single institution during the period 2010-2014. Patients were matched on unilateral/bilateral treatment, disease site, human papillomavirus status, T and N status, smoking status, and receipt of concomitant chemotherapy. Survival analyzes were performed using a Cox model and binary toxicity endpoints using a logistic regression analysis. RESULTS Fifty IMPT and 100 IMRT patients were included. The median follow-up time was 32months. There were no imbalances in patient/tumor characteristics except for age (mean age 56.8years for IMRT patients and 61.1years for IMPT patients, p-value=0.010). Statistically significant differences were not observed in overall survival (hazard ratio (HR)=0.55; 95% confidence interval (CI): 0.12-2.50, p-value=0.44) or in progression-free survival (HR=1.02; 95% CI: 0.41-2.54; p-value=0.96). The age-adjusted odds ratio (OR) for the presence of a gastrostomy (G)-tube during treatment for IMPT vs IMRT were OR=0.53; 95% CI: 0.24-1.15; p-value=0.11 and OR=0.43; 95% CI: 0.16-1.17; p-value=0.10 at 3months after treatment. When considering the pre-planned composite endpoint of grade 3 weight loss or G-tube presence, the ORs were OR=0.44; 95% CI: 0.19-1.0; p-value=0.05 at 3months after treatment and OR=0.23; 95% CI: 0.07-0.73; p-value=0.01 at 1year after treatment. CONCLUSION Our results suggest that IMPT is associated with reduced rates of feeding tube dependency and severe weight loss without jeopardizing outcome. Prospective multicenter randomized trials are needed to validate such findings.
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Affiliation(s)
- Pierre Blanchard
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA; Department of Radiation Oncology, Institut Gustave Roussy, Villejuif, France
| | - Adam S Garden
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - G Brandon Gunn
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - David I Rosenthal
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - William H Morrison
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Mike Hernandez
- Department of Quantitative Sciences, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Joseph Crutison
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Jack J Lee
- Department of Quantitative Sciences, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Rong Ye
- Department of Quantitative Sciences, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - C David Fuller
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA; Medical Physics Program, The University of Texas Graduate School of Biomedical Sciences, Houston, USA
| | - Abdallah S R Mohamed
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA; Department of Clinical Oncology and Nuclear Medicine, University of Alexandria, Egypt
| | - Kate A Hutcheson
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Emma B Holliday
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Nikhil G Thaker
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Erich M Sturgis
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Merrill S Kies
- Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - X Ronald Zhu
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Radhe Mohan
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, USA
| | - Steven J Frank
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA.
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