| Literature DB >> 27929477 |
Michelle K Nielsen1, Kyle E Malkoske, Erika Brown, Kevin Diamond, Normand Frenière, John Grant, Natalie Pomerleau-Dalcourt, Jason Schella, L John Schreiner, Laurent Tantôt, J Eduardo Villareal-Barajas, Jean-Pierre Bissonnette.
Abstract
A close partnership between the Canadian Partnership for Quality Radiotherapy (CPQR) and the Canadian Organization of Medical Physicist's (COMP) Quality Assurance and Radiation Safety Advisory Committee (QARSAC) has resulted in the development of a suite of Technical Quality Control (TQC) guidelines for radiation treatment equipment; they outline specific performance objectives and criteria that equipment should meet in order to assure an acceptable level of radiation treatment quality. The adopted framework for the development and maintenance of the TQCs ensures the guidelines incorporate input from the medical physics com-munity during development, measures the workload required to perform the QC tests outlined in each TQC, and remain relevant (i.e., "living documents") through subsequent planned reviews and updates. The framework includes consolidation of existing guidelines and/or literature by expert reviewers, structured stages of public review, external field-testing, and ratification by COMP. This TQC develop-ment framework is a cross-country initiative that allows for rapid development of robust, community-driven living guideline documents that are owned by the com-munity and reviewed to keep relevant in a rapidly evolving technical environment. Community engagement and uptake survey data shows 70% of Canadian centers are part of this process and that the data in the guideline documents reflect, and are influencing, the way Canadian radiation treatment centers run their technical quality control programs. For a medium-sized center comprising six linear accelerators and a comprehensive brachytherapy program, we evaluate the physics workload to 1.5 full-time equivalent physicists per year to complete all QC tests listed in this suite.Entities:
Mesh:
Year: 2016 PMID: 27929477 PMCID: PMC5690511 DOI: 10.1120/jacmp.v17i6.6422
Source DB: PubMed Journal: J Appl Clin Med Phys ISSN: 1526-9914 Impact factor: 2.102
Figure 1Revision cycles of the Technical Quality Control document review process.
List of documents available on http://www.cpqr.ca/programs/technical‐quality‐control/www.cpqr.ca. Accessed May 20, 2016
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| RED: Reference Dosimetry |
| PDM: Patient‐Specific Dosimetric Measurements for Modulated Therapies |
| SST: Safety System Technical Quality Control |
| GKR: Gamma Knife Radiosurgery |
| RDM: Data Management Systems |
| TOM: Helical Tomotherapy |
| 4DC: Four Dimensional Computed Tomography |
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| CTS: Computed Tomography Simulators |
| VMA: Volumetric Modulated Arc Therapy (incorporation into MLA) |
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| ACB: Accelerator Integrated Cone Beam Systems for Verification Imaging |
| LDR: Low Dose Rate Permanent Seed Brachytherapy |
| MLA: Medical Linear Accelerators and Multileaf Collimators |
| TPS: Treatment Planning Systems |
| HDR: Brachytherapy Remote Afterloaders |
| MDE: Major Dosimetry Equipment |
| CRS: Conventional Radiotherapy Simulators |
| KRM: Kilovoltage X‐ray Radiotherapy Machines |
| BRA: Brachytherapy Remote Afterloaders |
Figure 2Technical Quality Control document cumulative webpage hits September 2014 to August 2015.
Summary of regional download data from www.cpqr.ca between September 2014 and August 2015
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| Canada | 1486 | 72.1% |
| Europe | 204 | 9.9% |
| Asia | 145 | 7.0% |
| Africa | 99 | 4.8% |
| North America (excl. Canada) | 64 | 3.1% |
| Australia/Oceania | 54 | 2.6% |
| South America | 8 | 0.4% |
Figure 3Canadian map showing all radiotherapy centers. Red and Pink markers represent large and small external validation centers, respectively. Green markers represent centers where expert reviewers are employed. White makers indicate centers that have yet to contribute.
Sample comments and responses from community review of the MLA TQC guideline. Test acronyms are indicated in parentheses
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| Test DL7 (Room Radiation Monitors): We only have one radiation monitor in our treatment room. Should it be “Room radiation monitor” (no “s”)? |
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| When looking at positioning accuracy, in particular the laser/crosshair daily QC, was any consideration given to the tolerance for IMRT set by TG142 of 1.5 mm? |
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| It would appear that there are no open field profile or depth dose measurements in the annual tests but that the profile requirements for the monthly tests have been increased substantially. Is this your intent or is it an omission? TG142 does include annual tests for the change of flatness and symmetry from baseline for example. I am also not confident enough in our monthly profile measurement techniques to make significant beam adjustments based solely on these measurements and would thus continue to do annual measurements in a water tank. |
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| Test ML16 (Light/radiation coincidence): To my mind, the tolerance and action levels are too large. It should be 1 and 2 mm. |
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Sample comments and responses from external validation of the MLA (Medical Linear Accelerators and MLC) TQC guideline. Test acronyms are defined in parentheses
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| Test DL7 (Room radiation monitoring system): We believe that this system adds no benefit to security, nor quality, bearing in mind economic considerations, and should not be encouraged by the TQC guidelines. We suggest removing the test from TQC guideline. Similar comment received from a second institution during external validation. |
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| Citing an example procedure may clarify the implementation of certain tests. For example, it was not exactly clear from the description how Test AL14 (Coincidence of axes of rotation) and Test AL15 (Coincidence of radiation and mechanical isocentre) differ. The names may be mismatched from the description and the technical details of implementation could be clarified. |
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| Test AL1 (Profile reproducibility): The test description note does not specify the depth of measurement for electron beams, while it does for photon beams. We suggest specifying for both or remove it for photons. |
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Summary data and subset of questions from external review questionnaires (21 reports were submitted from 15 centers on 11 TQC documents), and percentage of tests (total number is 348 tests) that were commented for each section of the report
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| Do any of the tests specified require changes to either tolerances or frequency? | 15% (53/348) | Discussions or clarifications required for specific tests |
| Does your center have all the necessary resources to complete the tests outlined? Were all the tests performed? | 83% (289/348) | Human Resources and/or equipment availability factors |
| Are the tests appropriate and achievable? | 92% (320/348) | Related test specifications and vendor equipment differences |
| In your opinion, does the document address current practices and technologies? | 91% (19/21) | 2 centers did not answer |
Annual workload measurements, obtained from 18 external validation reports from centers on 9 TQC documents. Assumed test frequencies per year: daily 260, weekly 52, monthly 12, quarterly 4, annual 1, biennial one‐half
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| ACB | 2 | 123 | 118 | 129 |
| LDR | 2 | 262 | 220 | 304 |
| MLA | 2 | 197 | 164 | 230 |
| TPS | 2 | 10 | 10 | 11 |
| BRA | 2 | 159 | 94 | 224 |
| MDE | 2 | 25 | 15 | 35 |
| CRS | 2 | 98 | 70 | 125 |
| KRM | 2 | 190 | 158 | 223 |
| CTS | 2 | 90 | 78 | 102 |
Figure 4Percentage of respondents who made changes to their QA program following publication of the given TQC guideline. Respondents that did not possess the respective equipment were removed from the denominator.