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Fog LS, Webb LK, Barber J, Jennings M, Towns S, Olivera S, Shakeshaft J. ACPSEM position paper: pre-treatment patient specific plan checks and quality assurance in radiation oncology. Phys Eng Sci Med 2024; 47:7-15. [PMID: 38315415 DOI: 10.1007/s13246-023-01367-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 12/06/2023] [Indexed: 02/07/2024]
Abstract
The Australasian College of Physical Scientists and Engineers in Medicine (ACPSEM) has not previously made recommendations outlining the requirements for physics plan checks in Australia and New Zealand. A recent workforce modelling exercise, undertaken by the ACPSEM, revealed that the workload of a clinical radiation oncology medical physicist can comprise of up to 50% patient specific quality assurance activities. Therefore, in 2022 the ACPSEM Radiation Oncology Specialty Group (ROSG) set up a working group to address this issue. This position paper authored by ROSG endorses the recommendations of the American Association of Physicists in Medicine (AAPM) Task Group 218, 219 and 275 reports with some contextualisation for the Australia and New Zealand settings. A few recommendations from other sources are also endorsed to complete the position.
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Affiliation(s)
- Lotte S Fog
- Alfred Health Radiation Oncology, Melbourne, VIC, Australia.
| | | | - Jeffrey Barber
- Sydney West Radiation Oncology Network, Blacktown Hospital, Blacktown, NSW, 2148, Australia
| | - Matthew Jennings
- ICON Cancer Care, Cordelia St, South Brisbane, QLD, 4101, Australia
| | - Sam Towns
- Alfred Health Radiation Oncology, Melbourne, VIC, Australia
| | - Susana Olivera
- ICON Cancer Care, Liz Plummer Cancer Centre, Cairns, QLD, 4870, Australia
| | - John Shakeshaft
- ICON Cancer Care, Gold Coast University Hospital, 1 Hospital Blvd, Southport, QLD, 4215, Australia
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Lehmann J, Hussein M, Barry M, Siva S, Moore A, Chu M, Díez P, Eaton DJ, Harwood J, Lonski P, Claridge Mackonis E, Meehan C, Patel R, Ray X, Shaw M, Shepherd J, Smyth G, Standen TS, Subramanian B, Greer P, Clark CH. SEAFARER – A new concept for validating radiotherapy patient specific QA for clinical trials and clinical practice. Radiother Oncol 2022; 171:121-128. [DOI: 10.1016/j.radonc.2022.04.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 03/22/2022] [Accepted: 04/14/2022] [Indexed: 01/12/2023]
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Shaw M, Lye J, Alves A, Keehan S, Lehmann J, Hanlon M, Kenny J, Baines J, Porumb C, Geso M, Brown R. Characterisation of a synthetic diamond detector for end-to-end dosimetry in stereotactic body radiotherapy and radiosurgery. Phys Imaging Radiat Oncol 2021; 20:40-45. [PMID: 34722939 PMCID: PMC8536779 DOI: 10.1016/j.phro.2021.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 10/09/2021] [Accepted: 10/10/2021] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND AND PURPOSE Synthetic diamond detectors offer real time measurement of dose in radiotherapy applications which require high spatial resolution. Additional considerations and corrections are required for measurements where the diamond detector is orientated at various angles to the incident beam. This study investigated diamond detectors for end-to-end testing of Stereotactic Body Radiotherapy (SBRT) and Stereotactic Radiosurgery (SRS) in the context of dosimetry audits. MATERIAL AND METHODS Seven individual diamond detectors were investigated and compared with respect to warm up stability, dose-rate dependence, linearity, detector shadowing, energy response, cross-calibration, angular dependence and positional sensitivity in SBRT and SRS. RESULTS Large variation in the cross calibration factors was found between the seven individual detectors. For each detector, the energy dependence in the cross calibration factor was on average <0.6% across the beam qualities investigated (Co-60 Gamma Knife, and MV beams with TPR20,10 0.684-0.733). The angular corrections for individual fields were up to 5%, and varied with field size. However, the average angular dependence for all fields in a typical SRS treatment delivery was <1%. The overall measurement uncertainty was 3.6% and 3.1% (2σ) for an SRS and SBRT treatment plan respectively. CONCLUSION Synthetic diamond detectors were found to be reliable and robust for end-to-end dosimetry in SBRT and SRS applications. Orientation of the detector relative to the beam axis is an important consideration, as significant corrections are required for angular dependence.
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Affiliation(s)
- Maddison Shaw
- Australian Clinical Dosimetry Service, Australian Radiation Protection and Nuclear Safety Agency, Yallambie, VIC, Australia
- School of Health and Biomedical Science, RMIT University, Melbourne, VIC, Australia
| | - Jessica Lye
- Australian Clinical Dosimetry Service, Australian Radiation Protection and Nuclear Safety Agency, Yallambie, VIC, Australia
- Olivia Newtown John Cancer Wellness & Research Centre, Heidelberg, VIC, Australia
| | - Andrew Alves
- Australian Clinical Dosimetry Service, Australian Radiation Protection and Nuclear Safety Agency, Yallambie, VIC, Australia
| | - Stephanie Keehan
- Australian Clinical Dosimetry Service, Australian Radiation Protection and Nuclear Safety Agency, Yallambie, VIC, Australia
| | - Joerg Lehmann
- Department of Radiation Oncology, Calvary Mater Newcastle, Newcastle, Australia
- School of Science, RMIT University, Melbourne, Australia
- School of Mathematical and Physical Sciences, University of Newcastle, Australia
- Institute of Medical Physics, University of Sydney, Australia
| | - Maximilian Hanlon
- Australian Clinical Dosimetry Service, Australian Radiation Protection and Nuclear Safety Agency, Yallambie, VIC, Australia
| | - John Kenny
- Medical Physics Specialists, Health Stem Solutions, Melbourne, VIC, Australia
| | - John Baines
- Radiation Oncology, Townsville Cancer Centre, Townsville, QLD, Australia
| | - Claudiu Porumb
- Alfred Health Radiation Oncology, Melbourne VIC, Australia
| | - Moshi Geso
- School of Health and Biomedical Science, RMIT University, Melbourne, VIC, Australia
| | - Rhonda Brown
- Australian Clinical Dosimetry Service, Australian Radiation Protection and Nuclear Safety Agency, Yallambie, VIC, Australia
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Hughes J, Lye JE, Kadeer F, Alves A, Shaw M, Supple J, Keehan S, Gibbons F, Lehmann J, Kron T. Calculation algorithms and penumbra: Underestimation of dose in organs at risk in dosimetry audits. Med Phys 2021; 48:6184-6197. [PMID: 34287963 DOI: 10.1002/mp.15123] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 06/27/2021] [Accepted: 07/07/2021] [Indexed: 11/07/2022] Open
Abstract
PURPOSE The aim of this study is to investigate overdose to organs at risk (OARs) observed in dosimetry audits in Monte Carlo (MC) algorithms and Linear Boltzmann Transport Equation (LBTE) algorithms. The impact of penumbra modeling on OAR dose was assessed with the adjustment of MC modeling parameters and the clinical relevance of the audit cases was explored with a planning study of spine and head and neck (H&N) patient cases. METHODS Dosimetric audits performed by the Australian Clinical Dosimetry Service (ACDS) of 43 anthropomorphic spine plans and 1318 C-shaped target plans compared the planned dose to doses measured with ion chamber, microdiamond, film, and ion chamber array. An MC EGSnrc model was created to simulate the C-shape target case. The electron cut-off energy Ecut(kinetic) was set at 500, 200, and 10 keV, and differences between 1 and 3 mm voxel were calculated. A planning study with 10 patient stereotactic body radiotherapy (SBRT) spine plans and 10 patient H&N plans was calculated in both Acuros XB (AXB) v15.6.06 and Anisotropic Analytical Algorithm (AAA) v15.6.06. The patient contour was overridden to water as only the penumbral differences between the two different algorithms were under investigation. RESULTS The dosimetry audit results show that for the SBRT spine case, plans calculated in AXB are colder than what is measured in the spinal cord by 5%-10%. This was also observed for other audit cases where a C-shape target is wrapped around an OAR where the plans were colder by 3%-10%. Plans calculated with Monaco MC were colder than measurements by approximately 7% with the OAR surround by a C-shape target, but these differences were not noted in the SBRT spine case. Results from the clinical patient plans showed that the AXB was on average 7.4% colder than AAA when comparing the minimum dose in the spinal cord OAR. This average difference between AXB and AAA reduced to 4.5% when using the more clinically relevant metric of maximum dose in the spinal cord. For the H&N plans, AXB was cooler on average than AAA in the spinal cord OAR (1.1%), left parotid (1.7%), and right parotid (2.3%). The EGSnrc investigation also noted similar, but smaller differences. The beam penumbra modeled by Ecut(kinetic) = 500 keV was steeper than the beam penumbra modeled by Ecut(kinetic) = 10 keV as the full scatter is not accounted for, which resulted in less dose being calculated in a central OAR region where the penumbra contributes much of the dose. The dose difference when using 2.5 mm voxels of the center of the OAR between 500 and 10 keV was 3%, reducing to 1% between 200 and 10 keV. CONCLUSIONS Lack of full penumbral modeling due to approximations in the algorithms in MC based or LBTE algorithms are a contributing factor as to why these algorithms under-predict the dose to OAR when the treatment volume is wrapped around the OAR. The penumbra modeling approximations also contribute to AXB plans predicting colder doses than AAA in areas that are in the vicinity of beam penumbra. This effect is magnified in regions where there are many beam penumbras, for example in the spinal cord for spine SBRT cases.
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Affiliation(s)
- Jeremy Hughes
- Australian Clinical Dosimetry Service, ARPANSA, Yallambie, Victoria, Australia.,Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
| | - Jessica Elizabeth Lye
- Australian Clinical Dosimetry Service, ARPANSA, Yallambie, Victoria, Australia.,Physical Sciences, Olivia Newton-John Cancer Wellness Centre, Heidelberg, Victoria, Australia
| | - Fayz Kadeer
- Australian Clinical Dosimetry Service, ARPANSA, Yallambie, Victoria, Australia
| | - Andrew Alves
- Australian Clinical Dosimetry Service, ARPANSA, Yallambie, Victoria, Australia
| | - Maddison Shaw
- Australian Clinical Dosimetry Service, ARPANSA, Yallambie, Victoria, Australia.,Applied Sciences Physics Department, RMIT University, Melbourne, Victoria, Australia
| | - Jeremy Supple
- Australian Clinical Dosimetry Service, ARPANSA, Yallambie, Victoria, Australia
| | - Stephanie Keehan
- Australian Clinical Dosimetry Service, ARPANSA, Yallambie, Victoria, Australia.,Alfred Health Radiation Oncology, The Alfred Hospital, Melbourne, Victoria, Australia
| | - Francis Gibbons
- Australian Clinical Dosimetry Service, ARPANSA, Yallambie, Victoria, Australia.,Physical Sciences, Sunshine Coast University Hospital, Birtinya, Queensland, Australia
| | - Joerg Lehmann
- Applied Sciences Physics Department, RMIT University, Melbourne, Victoria, Australia.,Department of Radiation Oncology, Calvary Mater Newcastle, Newcastle, New South Wales, Australia.,School of Mathematical and Physical Sciences, University of Newcastle, Callaghan, New South Wales, Australia.,Institute of Medical Physics, University of Sydney, Camperdown, New South Wales, Australia
| | - Tomas Kron
- Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.,Applied Sciences Physics Department, RMIT University, Melbourne, Victoria, Australia
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Shaw M, Lye J, Alves A, Hanlon M, Lehmann J, Supple J, Porumb C, Williams I, Geso M, Brown R. Measuring the dose in bone for spine stereotactic body radiotherapy. Phys Med 2021; 84:265-273. [PMID: 33773909 DOI: 10.1016/j.ejmp.2021.03.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 02/08/2021] [Accepted: 03/05/2021] [Indexed: 11/29/2022] Open
Abstract
PURPOSE Current quality assurance of radiotherapy involving bony regions generally utilises homogeneous phantoms and dose calculations, ignoring the challenges of heterogeneities with dosimetry problems likely occurring around bone. Anthropomorphic phantoms with synthetic bony materials enable realistic end-to-end testing in clinical scenarios. This work reports on measurements and calculated corrections required to directly report dose in bony materials in the context of comprehensive end-to-end dosimetry audit measurements (63 plans, 6 planning systems). MATERIALS AND METHODS Radiochromic film and microDiamond measurements were performed in an anthropomorphic spine phantom containing bone equivalent materials. Medium dependent correction factors, kmed, were established using 6 MV and 10 MV Linear Accelerator Monte Carlo simulations to account for the detectors being calibrated in water, but measuring in regions of bony material. Both cortical and trabecular bony material were investigated for verification of dose calculations in dose-to-medium (Dm,m) and dose-to-water (Dw,w) scenarios. RESULTS For Dm,m calculations, modelled correction factors for cortical and trabecular bone in film measurements, and for trabecular bone in microDiamond measurements were 0.875(±0.1%), 0.953(±0.3%) and 0.962(±0.4%), respectively. For Dw,w calculations, the corrections were 0.920(±0.1%), 0.982(±0.3%) and 0.993(±0.4%), respectively. In the audit, application of the correction factors improves the mean agreement between treatment plans and measured microDiamond dose from -2.4%(±3.9%) to 0.4%(±3.7%). CONCLUSION Monte Carlo simulations provide a method for correcting the dose measured in bony materials allowing more accurate comparison with treatment planning system doses. In verification measurements, algorithm specific correction factors should be applied to account for variations in bony material for calculations based on Dm,m and Dw,w.
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Affiliation(s)
- Maddison Shaw
- Australian Clinical Dosimetry Service, Australian Radiation Protection and Nuclear Safety Agency, Melbourne, Australia; School of Health and Biomedical Sciences, RMIT University, Melbourne, Australia.
| | - Jessica Lye
- Australian Clinical Dosimetry Service, Australian Radiation Protection and Nuclear Safety Agency, Melbourne, Australia; Olivia Newton John Cancer Wellness Centre, Melbourne, Australia
| | - Andrew Alves
- Australian Clinical Dosimetry Service, Australian Radiation Protection and Nuclear Safety Agency, Melbourne, Australia
| | - Maximilian Hanlon
- Primary Standards Dosimetry Laboratory, ARPANSA, Melbourne, Australia
| | - Joerg Lehmann
- Department of Radiation Oncology, Calvary Mater Newcastle, Newcastle, Australia; School of Science, RMIT University, Melbourne, Australia; School of Mathematical and Physical Sciences, University of Newcastle, Australia; Institute of Medical Physics, University of Sydney, Australia
| | - Jeremy Supple
- Australian Clinical Dosimetry Service, Australian Radiation Protection and Nuclear Safety Agency, Melbourne, Australia
| | - Claudiu Porumb
- Alfred Health Radiation Oncology, The Alfred Hospital, Melbourne, Australia
| | - Ivan Williams
- Australian Radiation Protection and Nuclear Safety Agency, Melbourne, Australia
| | - Moshi Geso
- School of Health and Biomedical Sciences, RMIT University, Melbourne, Australia
| | - Rhonda Brown
- Australian Clinical Dosimetry Service, Australian Radiation Protection and Nuclear Safety Agency, Melbourne, Australia
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Gronberg MP, Tailor RC, Smith SA, Kry SF, Followill DS, Stojadinovic S, Niedzielski JS, Lindsay PE, Krishnan S, Aguirre F, Fujimoto TN, Taniguchi CM, Howell RM. A Mail Audit Independent Peer Review System for Dosimetry Verification of a Small Animal Irradiator. Radiat Res 2020; 193:341-350. [PMID: 32068498 DOI: 10.1667/rr15220.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Dedicated precision orthovoltage small animal irradiators have become widely available in the past decade and are commonly used for radiation biology research. However, there is a lack of dosimetric standardization among these irradiators, which affects the reproducibility of radiation-based animal studies. The purpose of this study was to develop a mail-based, independent peer review system to verify dose delivery among institutions using X-RAD 225Cx irradiators (Precision X-Ray, North Branford, CT). A robust, user-friendly mouse phantom was constructed from high-impact polystyrene and designed with dimensions similar to those of a typical laboratory mouse. The phantom accommodates three thermoluminescent dosimeters (TLDs) to measure dose. The mouse peer review system was commissioned in a small animal irradiator using anterior-posterior and posterior-anterior beams of 225 kVp and then mailed to three institutions to test the feasibility of the audit service. The energy correction factor for TLDs in the mouse phantom was derived to validate the delivered dose using this particular animal irradiation system. This feasibility study indicated that three institutions were able to deliver a radiation dose to the mouse phantom within ±10% of the target dose. The developed mail audit independent peer review system for the verification of mouse dosimetry can be expanded to characterize other commercially available orthovoltage irradiators, thereby enhancing the reproducibility of studies employing these irradiators.
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Affiliation(s)
- Mary P Gronberg
- Departments of Radiation Physics.,Departments of The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Ramesh C Tailor
- Departments of Radiation Physics.,Departments of The University of Texas MD Anderson Cancer Center, Houston, Texas
| | | | - Stephen F Kry
- Departments of Radiation Physics.,Departments of The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - David S Followill
- Departments of Radiation Physics.,Departments of The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Strahinja Stojadinovic
- Departments of Radiation Oncology.,Departments of Health Care Sciences, The University of Texas Southwestern Medical Center, Dallas, Texas
| | | | - Patricia E Lindsay
- Departments of Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Ontario, Canada.,Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada
| | - Sunil Krishnan
- Departments of Radiation Oncology, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Science, Houston, Texas.,Departments of The University of Texas MD Anderson Cancer Center, Houston, Texas
| | | | - Tara N Fujimoto
- Departments of Radiation Oncology, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Science, Houston, Texas
| | - Cullen M Taniguchi
- Departments of Radiation Oncology, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Science, Houston, Texas.,Departments of The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Rebecca M Howell
- Departments of Radiation Physics.,Departments of The University of Texas MD Anderson Cancer Center, Houston, Texas
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Dunn L, Jolly D. Automated data mining of a plan-check database and example application. J Appl Clin Med Phys 2018; 19:739-748. [PMID: 29956454 PMCID: PMC6123163 DOI: 10.1002/acm2.12396] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 04/15/2018] [Accepted: 05/24/2018] [Indexed: 12/02/2022] Open
Abstract
Purpose The aim of this work was to present the development and example application of an automated data mining software platform that preforms bulk analysis of results and patient data passing through the 3D plan and delivery QA system, Mobius3D. Methods Python, matlab, and Java were used to create an interface that reads JavaScript Object Notation (JSON) created for every approved Mobius3D pre‐treatment plan‐check. The aforementioned JSON files contain all the information for every pre‐treatment QA check performed by Mobius3D, including all 3D dose, CT, structure set information, as well as all plan information and patient demographics. Two Graphical User Interfaces (GUIs) were created, the first is called Mobius3D‐Database (M3D‐DB) and presents the check results in both filterable tabular and graphical form. These data are presented for all patients and includes mean dose differences, 90% coverage, 3D gamma pass rate percentages, treatment sites, machine, beam energy, Multi‐Leaf Collimator (MLC) mode, treatment planning system (TPS), plan names, approvers, dates and times. Group statistics and statistical process control levels are then calculated based on filter settings. The second GUI, called Mobius3D organ at risk (M3DOAR), analyzes dose‐volume histogram data for all patients and all Organs‐at‐Risk (OAR). The design of the software is such that all treatment parameters and treatment site information are able to be filtered and sorted with the results, plots, and statistics updated. Results The M3D‐DB software can summarize and filter large numbers of plan‐checks from Mobius3D. The M3DOAR software is also able to analyze large amounts of dose‐volume data for patient groups which may prove useful in clinical trials, where OAR doses for large numbers of patients can be compared and correlated. Target DVHs can also be analyzed en mass. Conclusions This work demonstrates a method to extract the large amount of treatment data for every patient that is stored by Mobius3D but not easily accessible. With scripting, it is possible to mine this data for research and clinical trials as well as patient and TPS QA.
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Affiliation(s)
- Leon Dunn
- Icon Cancer Centre - The Valley, Mulgrave, Melbourne, Vic, Australia
| | - David Jolly
- Icon Cancer Centre - Richmond, Richmond, Melbourne, Vic, Australia
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Lehmann J, Alves A, Dunn L, Shaw M, Kenny J, Keehan S, Supple J, Gibbons F, Manktelow S, Oliver C, Kron T, Williams I, Lye J. Dosimetric end-to-end tests in a national audit of 3D conformal radiotherapy. Phys Imaging Radiat Oncol 2018; 6:5-11. [PMID: 33458381 PMCID: PMC7807562 DOI: 10.1016/j.phro.2018.03.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 03/14/2018] [Accepted: 03/14/2018] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Independent dosimetry audits improve quality and safety of radiation therapy. This work reports on design and findings of a comprehensive 3D conformal radiotherapy (3D-CRT) Level III audit. MATERIALS AND METHODS The audit was conducted as onsite audit using an anthropomorphic thorax phantom in an end-to-end test by the Australian Clinical Dosimetry Service (ACDS). Absolute dose point measurements were performed with Farmer-type ionization chambers. The audited treatment plans included open and half blocked fields, wedges and lung inhomogeneities. Audit results were determined as Pass Optimal Level (deviations within 3.3%), Pass Action Level (greater than 3.3% but within 5%) and Out of Tolerance (beyond 5%), as well as Reported Not Scored (RNS). The audit has been performed between July 2012 and January 2018 on 94 occasions, covering approximately 90% of all Australian facilities. RESULTS The audit pass rate was 87% (53% optimal). Fifty recommendations were given, mainly related to planning system commissioning. Dose overestimation behind low density inhomogeneities by the analytical anisotropic algorithm (AAA) was identified across facilities and found to extend to beam setups which resemble a typical breast cancer treatment beam placement. RNS measurements inside lung showed a variation in the opposite direction: AAA under-dosed a target beyond lung and over-dosed the lung upstream and downstream of the target. Results also highlighted shortcomings of some superposition and convolution algorithms in modelling large angle wedges. CONCLUSIONS This audit showed that 3D-CRT dosimetry audits remain relevant and can identify fundamental global and local problems that also affect advanced treatments.
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Affiliation(s)
- Joerg Lehmann
- Australian Clinical Dosimetry Service (ACDS), Australian Radiation Protection and National Safety Agency (ARPANSA), 619 Lower Plenty Road, Yallambie, VIC 3085, Australia
- Institute of Medical Physics, School of Physics A28, University of Sydney NSW 2006, Australia
- School of Mathematical and Physical Sciences, The University of Newcastle, University Drive, Callaghan, NSW 2308, Australia
- School of Science, Royal Melbourne Institute of Technology (RMIT) University, 124 La Trobe Street, Melbourne, VIC 3000, Australia
| | - Andrew Alves
- Australian Clinical Dosimetry Service (ACDS), Australian Radiation Protection and National Safety Agency (ARPANSA), 619 Lower Plenty Road, Yallambie, VIC 3085, Australia
| | - Leon Dunn
- Australian Clinical Dosimetry Service (ACDS), Australian Radiation Protection and National Safety Agency (ARPANSA), 619 Lower Plenty Road, Yallambie, VIC 3085, Australia
| | - Maddison Shaw
- Australian Clinical Dosimetry Service (ACDS), Australian Radiation Protection and National Safety Agency (ARPANSA), 619 Lower Plenty Road, Yallambie, VIC 3085, Australia
- School of Science, Royal Melbourne Institute of Technology (RMIT) University, 124 La Trobe Street, Melbourne, VIC 3000, Australia
| | - John Kenny
- Australian Clinical Dosimetry Service (ACDS), Australian Radiation Protection and National Safety Agency (ARPANSA), 619 Lower Plenty Road, Yallambie, VIC 3085, Australia
| | - Stephanie Keehan
- Australian Clinical Dosimetry Service (ACDS), Australian Radiation Protection and National Safety Agency (ARPANSA), 619 Lower Plenty Road, Yallambie, VIC 3085, Australia
- School of Science, Royal Melbourne Institute of Technology (RMIT) University, 124 La Trobe Street, Melbourne, VIC 3000, Australia
| | - Jeremy Supple
- Australian Clinical Dosimetry Service (ACDS), Australian Radiation Protection and National Safety Agency (ARPANSA), 619 Lower Plenty Road, Yallambie, VIC 3085, Australia
| | - Francis Gibbons
- Australian Clinical Dosimetry Service (ACDS), Australian Radiation Protection and National Safety Agency (ARPANSA), 619 Lower Plenty Road, Yallambie, VIC 3085, Australia
| | - Sophie Manktelow
- Australian Clinical Dosimetry Service (ACDS), Australian Radiation Protection and National Safety Agency (ARPANSA), 619 Lower Plenty Road, Yallambie, VIC 3085, Australia
| | - Chris Oliver
- Australian Clinical Dosimetry Service (ACDS), Australian Radiation Protection and National Safety Agency (ARPANSA), 619 Lower Plenty Road, Yallambie, VIC 3085, Australia
| | - Tomas Kron
- Australian Clinical Dosimetry Service (ACDS), Australian Radiation Protection and National Safety Agency (ARPANSA), 619 Lower Plenty Road, Yallambie, VIC 3085, Australia
- School of Science, Royal Melbourne Institute of Technology (RMIT) University, 124 La Trobe Street, Melbourne, VIC 3000, Australia
- Department of Radiation Oncology, Peter MacCallum Cancer Center, 305 Grattan Street, Melbourne, VIC 3000, Australia
| | - Ivan Williams
- Australian Clinical Dosimetry Service (ACDS), Australian Radiation Protection and National Safety Agency (ARPANSA), 619 Lower Plenty Road, Yallambie, VIC 3085, Australia
| | - Jessica Lye
- Australian Clinical Dosimetry Service (ACDS), Australian Radiation Protection and National Safety Agency (ARPANSA), 619 Lower Plenty Road, Yallambie, VIC 3085, Australia
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Miri N, Lehmann J, Legge K, Vial P, Greer PB. Virtual EPID standard phantom audit (VESPA) for remote IMRT and VMAT credentialing. Phys Med Biol 2017; 62:4293-4299. [PMID: 28248642 DOI: 10.1088/1361-6560/aa63df] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A virtual EPID standard phantom audit (VESPA) has been implemented for remote auditing in support of facility credentialing for clinical trials using IMRT and VMAT. VESPA is based on published methods and a clinically established IMRT QA procedure, here extended to multi-vendor equipment. Facilities are provided with comprehensive instructions and CT datasets to create treatment plans. They deliver the treatment directly to their EPID without any phantom or couch in the beam. In addition, they deliver a set of simple calibration fields per instructions. Collected EPID images are uploaded electronically. In the analysis, the dose is projected back into a virtual cylindrical phantom. 3D gamma analysis is performed. 2D dose planes and linear dose profiles are provided and can be considered when needed for clarification. In addition, using a virtual flat-phantom, 2D field-by-field or arc-by-arc gamma analyses are performed. Pilot facilities covering a range of planning and delivery systems have performed data acquisition and upload successfully. Advantages of VESPA are (1) fast turnaround mainly driven by the facility's capability of providing the requested EPID images, (2) the possibility for facilities performing the audit in parallel, as there is no need to wait for a phantom, (3) simple and efficient credentialing for international facilities, (4) a large set of data points, and (5) a reduced impact on resources and environment as there is no need to transport heavy phantoms or audit staff. Limitations of the current implementation of VESPA for trials credentialing are that it does not provide absolute dosimetry, therefore a Level I audit is still required, and that it relies on correctly delivered open calibration fields, which are used for system calibration. The implemented EPID based IMRT and VMAT audit system promises to dramatically improve credentialing efficiency for clinical trials and wider applications.
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Affiliation(s)
- Narges Miri
- School of Mathematical and Physical Sciences, The University of Newcastle, Newcastle, Australia
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10
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Lye JE, Butler DJ, Oliver CP, Alves A, Lehmann J, Gibbons FP, Williams IM. Comparison between the TRS-398 code of practice and the TG-51 dosimetry protocol for flattening filter free beams. Phys Med Biol 2016; 61:N362-72. [DOI: 10.1088/0031-9155/61/14/n362] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Kron T, Lehmann J, Greer PB. Dosimetry of ionising radiation in modern radiation oncology. Phys Med Biol 2016; 61:R167-205. [DOI: 10.1088/0031-9155/61/14/r167] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Lye J, Kenny J, Lehmann J, Dunn L, Kron T, Alves A, Cole A, Williams I. A 2D ion chamber array audit of wedged and asymmetric fields in an inhomogeneous lung phantom. Med Phys 2015; 41:101712. [PMID: 25281951 DOI: 10.1118/1.4896097] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
PURPOSE The Australian Clinical Dosimetry Service (ACDS) has implemented a new method of a nonreference condition Level II type dosimetric audit of radiotherapy services to increase measurement accuracy and patient safety within Australia. The aim of this work is to describe the methodology, tolerances, and outcomes from the new audit. METHODS The ACDS Level II audit measures the dose delivered in 2D planes using an ionization chamber based array positioned at multiple depths. Measurements are made in rectilinear homogeneous and inhomogeneous phantoms composed of slabs of solid water and lung. Computer generated computed tomography data sets of the rectilinear phantoms are supplied to the facility prior to audit for planning of a range of cases including reference fields, asymmetric fields, and wedged fields. The audit assesses 3D planning with 6 MV photons with a static (zero degree) gantry. Scoring is performed using local dose differences between the planned and measured dose within 80% of the field width. The overall audit result is determined by the maximum dose difference over all scoring points, cases, and planes. Pass (Optimal Level) is defined as maximum dose difference ≤3.3%, Pass (Action Level) is ≤5.0%, and Fail (Out of Tolerance) is >5.0%. RESULTS At close of 2013, the ACDS had performed 24 Level II audits. 63% of the audits passed, 33% failed, and the remaining audit was not assessable. Of the 15 audits that passed, 3 were at Pass (Action Level). The high fail rate is largely due to a systemic issue with modeling asymmetric 60° wedges which caused a delivered overdose of 5%-8%. CONCLUSIONS The ACDS has implemented a nonreference condition Level II type audit, based on ion chamber 2D array measurements in an inhomogeneous slab phantom. The powerful diagnostic ability of this audit has allowed the ACDS to rigorously test the treatment planning systems implemented in Australian radiotherapy facilities. Recommendations from audits have led to facilities modifying clinical practice and changing planning protocols.
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Affiliation(s)
- Jessica Lye
- Australian Clinical Dosimetry Service, Yallambie, Victoria 3085, Australia
| | - John Kenny
- Australian Clinical Dosimetry Service, Yallambie, Victoria 3085, Australia and Radiation Oncology Queensland, Toowoomba, Queensland 4350, Australia
| | - Joerg Lehmann
- Australian Clinical Dosimetry Service, Yallambie, Victoria 3085, Australia and School of Applied Science, RMIT University, Melbourne 3000, Australia
| | - Leon Dunn
- Australian Clinical Dosimetry Service, Yallambie, Victoria 3085, Australia
| | - Tomas Kron
- School of Applied Science, RMIT University, Melbourne 3000, Australia and Peter MacCallum Cancer Centre, Melbourne 3008, Australia
| | - Andrew Alves
- Australian Clinical Dosimetry Service, Yallambie, Victoria 3085, Australia
| | - Andrew Cole
- Australian Clinical Dosimetry Service, Yallambie, Victoria 3085, Australia and Australian Radiation Protection and Nuclear Safety Agency, Yallambie, Victoria 3085, Australia
| | - Ivan Williams
- Australian Clinical Dosimetry Service, Yallambie, Victoria 3085, Australia and School of Applied Science, RMIT University, Melbourne 3000, Australia
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Kron T, Dwyer M, Smith L, MacDonald A, Pawsey M, Raik E, Arnold A, Hill B, Duchesne GM. The development of practice standards for radiation oncology in Australia: a tripartite approach. Clin Oncol (R Coll Radiol) 2015; 27:325-9. [PMID: 25669589 DOI: 10.1016/j.clon.2015.01.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 01/07/2015] [Accepted: 01/08/2015] [Indexed: 10/24/2022]
Abstract
In many areas of health care, practice standards have become an accepted method for professions to assess and improve the quality of care delivery. The aim of this work is to present the development of practice standards for radiation oncology in Australia, highlighting critical points and lessons learned. Following a review of radiotherapy services in Australia, a multidisciplinary group with support from the Australian Government developed practice standards for radiation oncology in Australia. The standards were produced in a multistep process including a nationwide survey of radiotherapy centres and piloting of the standards in a representative subset of all Australian radiotherapy centres. The standards are grouped into three sections: Facility management (covering staffing, data management, equipment and processes); Treatment planning and delivery (providing more detailed guidance on prescription, planning and delivery); Safety and quality management (including radiation safety, incident monitoring and clinical trials participation). Each of the 16 standards contains specific criteria, a commentary and suggestions for the evidence required to demonstrate compliance. The development of the standards was challenging and time consuming, but the collaborative efforts of the professions resulted in standards applicable throughout Australia and possibly further afield.
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Affiliation(s)
- T Kron
- Peter MacCallum Cancer Centre, Departments of Radiation Oncology and Physical Sciences, Melbourne, Victoria, Australia; Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, Victoria, Australia.
| | - M Dwyer
- Peter MacCallum Cancer Centre, Departments of Radiation Oncology and Physical Sciences, Melbourne, Victoria, Australia
| | - L Smith
- William Buckland Radiotherapy Centre, Melbourne, Australia
| | | | - M Pawsey
- Australian Institute of Health Innovation, University of New South Wales, Sydney, Australia
| | - E Raik
- National Pathology Accreditation Advisory Council, Australia
| | - A Arnold
- Illawarra Shoalhaven Local Health District, Australia
| | - B Hill
- Genesis CancerCare Queensland, Southport, Queensland, Australia
| | - G M Duchesne
- Peter MacCallum Cancer Centre, Departments of Radiation Oncology and Physical Sciences, Melbourne, Victoria, Australia; Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, Victoria, Australia
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Clark CH, Hussein M, Tsang Y, Thomas R, Wilkinson D, Bass G, Snaith J, Gouldstone C, Bolton S, Nutbrown R, Venables K, Nisbet A. A multi-institutional dosimetry audit of rotational intensity-modulated radiotherapy. Radiother Oncol 2014; 113:272-8. [DOI: 10.1016/j.radonc.2014.11.015] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 11/04/2014] [Accepted: 11/06/2014] [Indexed: 11/26/2022]
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Lehmann J, Kenny J, Lye J, Dunn L, Williams I. Trust, but verify – Accuracy of clinical commercial radiation Treatment Planning Systems. ACTA ACUST UNITED AC 2014. [DOI: 10.1088/1742-6596/489/1/012094] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Ibbott GS, Haworth A, Followill DS. Quality assurance for clinical trials. Front Oncol 2013; 3:311. [PMID: 24392352 PMCID: PMC3867736 DOI: 10.3389/fonc.2013.00311] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Accepted: 12/05/2013] [Indexed: 11/13/2022] Open
Abstract
Cooperative groups, of which the Radiation Therapy Oncology Group is one example, conduct national clinical trials that often involve the use of radiation therapy. In preparation for such a trial, the cooperative group prepares a protocol to define the goals of the trial, the rationale for its design, and the details of the treatment procedure to be followed. The Radiological Physics Center (RPC) is one of several quality assurance (QA) offices that is charged with assuring that participating institutions deliver doses that are clinically consistent and comparable. The RPC does this by conducting a variety of independent audits and credentialing processes. The RPC has compiled data showing that credentialing can help institutions comply with the requirements of a cooperative group clinical protocol. Phantom irradiations have been demonstrated to exercise an institution's procedures for planning and delivering advanced external beam techniques (1-3). Similarly, RPC data indicate that a rapid review of patient treatment records or planning procedures can improve compliance with clinical trials (4). The experiences of the RPC are presented as examples of the contributions that a national clinical trials QA center can make to cooperative group trials. These experiences illustrate the critical need for comprehensive QA to assure that clinical trials are successful and cost-effective. The RPC is supported by grants CA 10953 and CA 81647 from the National Cancer Institute, NIH, DHHS.
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Affiliation(s)
- Geoffrey S Ibbott
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center , Houston, TX , USA
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Kron T, Haworth A, Williams I. Dosimetry for audit and clinical trials: challenges and requirements. ACTA ACUST UNITED AC 2013. [DOI: 10.1088/1742-6596/444/1/012014] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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