QA in Radiation Medicine for Sustainable Health Care JAPM November 2023 Yakov Pipman DSc What is Quality in RT Risks Quality Assurance Program Equipment Treatment Delivery The degree to which radiation therapy is consistent with current professional knowledge ID: 1046039
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1. Quality Assurance in RadiotherapyQA in Radiation Medicine for Sustainable Health CareJAPMNovember 2023Yakov Pipman, DSc
2. What is Quality in RT?RisksQuality Assurance ProgramEquipmentTreatment Delivery
3. The degree to which radiation therapy is consistent with current professional knowledgeThe prescription is appropriate, i.e. evidence basedThe prescription is delivered within tolerances determined by consensus in the profession3Quality in Radiotherapy
4. Evidence from dose response curvesTumor Control Probability (TCP)Normal Tissue Complication Probability (NTCP).
5. Clinical requirements on accuracy in RTAbsolute absorbed doseSpatial distribution of dose
6. Effects of Geometric uncertainties:In target volumes: Underdosing of the required volume (decreases the TCP)In organs at risk: Overdosing of nearby structures (increases the NTCP)
7. The absence of an unacceptable risk of harm.What is harm in RT?excess morbidity sub-optimal tumour control.What is Safety ?
8. “Serious” Incidents per course of RTNew York State0.012%Varian 0.002%UK0.003%Is Safety an issue in Radiotherapy?The chance of dying or being injured on a U.S. domestic flight is about 0.00001% - Ford and Terezakis IJROBP 2010
9. IAEA has analyzed a series of accidental exposures in radiotherapy to draw lessons in methods for prevention of such occurrences.Criteria for classifying them:Direct causes of mis-administrationsContributing factorsPreventability of misadministrationClassification of potential hazard.
10. Accidents in radiotherapy - examplesCauseNumberCauseNumberCalculation error of time or dose15Human error during simulation2Inadequate review of patient chart9Decommissioning of teletherapy source error 2Error in anatomical area to be treated8Error in commissioning of TPS2Error in identifying the correct patient4Technologist misread the treatment time or MU2Error involving lack of/or misuse of a wedge4Malfunction of accelerator1Error in calibration of cobalt-60 source3Treatment unit mechanical failure1Transcription error of prescribed dose3Accelerator software error1Wrong repair followed by human error1
11. There are about 750,000 patients receiving RT per year in the U.S.How many patients fall into the “Quality Trap”?At 0.01% that would be 75 serious accidents per year in the US alone!If we ignore retreats, that is approximately 750,000 courses per year. 2.6% of 750,000 is about 20,000 in the “Quality Trap”Qualit trapyQuality trap
12. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.1.1. Slide 1Quality Assurance (QA) termsQuality AssuranceQuality ControlQuality StandardsQA in RadiotherapyQuality System
13. Planned and systematic actions to provide confidence that a product or service will satisfy the requirements for quality. proceduresactivitiesactionsgroups of staffThe management of a QA program is also called a Quality System Management.Quality Assurance
14. A regulatory process to:Measure performanceCompare with standardsAct to keep, or regain, conformance with standards. Quality control is a part of quality system management.It is concerned with operational techniques and activitiesQuality Control
15. Consists of the organizational structure responsibilities proceduresprocesses and resources as required to implement a quality assurance program. Quality System
16. Objectives of a QA program in RT :Reduction of uncertainties and errors (in dosimetry, treatment planning, equipment performance, treatment delivery)Reduction of chance of accidents and errors occurring, and increase the probability to detect and rectify soonerProviding reliable inter-comparison of results among different radiotherapy centersFull exploitation of improved technology and more complex treatments in modern radiotherapy
17. QA Programme in RT- Guidelines
18. In Radiotherapy:Responsibilities are shared and must be clearly defined. Each specialty group has an important part in the output of the entire processSpecific QA roles are interdependent, requiring close cooperation and quality controls.
19. Includesclinical radiation oncology servicesupportive care services (nursing, dietary, social, etc.)all issues related to radiation treatmentradiation therapistsphysical quality assurance (QA and QC) by physicistsengineering maintenancemanagementCovers all activities in the radiotherapy department:Starting from the moment a patient enters it until the moment he leaves, and continuing into the follow-up period.A Quality System in Radiotherapy
20. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.2.2. Slide 2Quality system/comprehensive QA programThe patient enters the process seeking treatmentThe patient leaves the department after treatmentThe outcome can be considered to be of good quality when the handling of the quality system well organizes the five aspects shown in the illustration above. InputOutputControlMeasureControlMeasureQA control process control policy & organization equipment knowledge &expertise QA SystemProcess
21. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.2.2. Slide 312.2 MANAGING A QUALITY ASSURANCE PROGRAMME 12.2.2 Quality system/comprehensive QA programA comprehensive quality system in radio-therapy is a management system that:Should be supported by the department management to work effectively.Must have a clear definition of its scope and of all the quality standards to be met.Must be regularly reviewed as to operation and improvement. A QA committee representing all the different disciplines, is required.Must be consistent in standards for different areas of the program.policy & organization
22. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.2.2. Slide 10When starting a QA program, setting up a QA team or QA committee is the most important first step.The QA team should reflect the composition of the multidisciplinary radiotherapy team.The quality assurance committee must be appointed by the department management/head of department with the authority to manage quality assurance.
23. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.2.2. Slide 512.2 MANAGING A QUALITY ASSURANCE PROGRAMME 12.2.2 Quality system/comprehensive QA programRequires that each staff member has qualifications (education, training and experience) appropriate to his or her role and responsibility.Requires that each staff member has access to appropriate opportunities for continuing education and development.
24. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.2.2. Slide 612.2 MANAGING A QUALITY ASSURANCE PROGRAMME 12.2.2 Quality system/comprehensive QA programRequires a formal written quality assurance program detailing the QA policies and procedures, quality control tests, frequencies, tolerances, action criteria, required records and personnel.Must be consistent in standards for different areas of the program.Must incorporate compliance with all the requirements of national legislation, accreditation, etc.
25. The formal written quality assurance program is also referred to as the "Quality Manual“, and it serves two purposes:Externally to collaborators in other departments, in management and in other institutions, to indicate that the department is strongly concerned with quality. Internally, it provides the department with a framework for further development of quality and for improvements of existing or new procedures.The Quality Manual
26. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.2.2. Slide 11Example for the organizational structure of a radiotherapy department and the integration of a QA teamSystematic Treatment ProgramRadiation Treatment ProgramManagement Services............QA Team (Committee)PhysicsRadiation OncologyRadiation TherapyChief Executive Officer
27. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.2.2. Slide 12Membership and Responsibilities Membership:Radiation Oncologist(s)Medical Physicist(s)Radiation Therapist(s)Nurse(s)..........Chair:Physicist orRadiation Oncologist Responsibilities:Patient safetyPersonnel safetyDosimetry instrumentationTeletherapy equipmentTreatment planningTreatment deliveryTreatment outcomeQuality auditQA Team (Committee)
28. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.3.1. Slide 1(1) Initial specification, acceptance testing and commissioningfor clinical use, including calibration where applicable(2) Quality control testsbefore the equipment is put into clinical use, quality control tests should be established and a formal QC program initiated General structure of a QA program for equipment(3) Additional quality control tests after any significant repair, intervention or adjustment or when there is any indication of a change in performance(4) Planned preventive maintenance programin accordance with the manufacturer’s recommendations
29. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.2.2. Slide 412.2 MANAGING A QUALITY ASSURANCE PROGRAMME 12.2.2 Quality system/comprehensive QA programA comprehensive quality system in radio-therapy is a management system that: Requires availability of adequate test equipment (more on that in the next talk)
30. QA Programme for RT Equipment – some Guidelines
31. AMERICAN ASSOCIATION OF PHYSICISTS IN MEDICINE (AAPM), “Comprehensive QA for radiation oncology: Report of AAPM Radiation Therapy Committee Task Group 40”, Med. Phys. 21, 581-618 (1994)INTERNATIONAL ELECTROTECHNICAL COMMISSION (IEC), “Medical electrical equipment - Medical electron accelerators-Functional performance characteristics”, IEC 976, IEC, Geneva, Switzerland (1989)INSTITUTE OF PHYSICS AND ENGINEERING IN MEDICINE (IPEM), “Physics aspects of quality control in radiotherapy”, IPEM Report 81, edited by Mayles, W.P.M., Lake, R., McKenzie, A., Macaulay, E.M., Morgan, H.M., Jordan, T.J. and Powley, S.K, IPEM, York, United Kingdom (1999)VAN DYK, J., (editor), “The Modern Technology for Radiation Oncology: A Compendium for Medical Physicists and Radiation Oncologists”, Medical Physics Publishing, Madison, Wisconsin, U.S.A. (1999)WILLIAMS, J.R., and THWAITES, D.I., (editors), “Radiotherapy Physics in Practice”, Oxford University Press, Oxford, United Kingdom (2000)QA programme for equipment- Sources
32. Equipment specification and clinical needs assessmentA detailed specification document in preparation for procurement of equipment, A multidisciplinary team from the department should be involved.This should set out the essential aspects of the equipment operation, facilities, performance, service, etc., as required by the user.
33. Acceptance The process in which the supplier demonstrates the baseline performance of the equipment to the customer. The essential performance required and expected from the machine should be agreed upon before acceptance of the equipment begins.After installation, the equipment must be tested to ensure that it meets the specifications, and that the environment is free of radiation and electrical hazards to staff and patients.
34. CommissioningThe process of preparing the equipment for clinical service.Full characterization of its performance over the whole range of possible operation.Establishes the baseline standards of performance to which all future performance and quality control tests will be referred.Includes the preparation of procedures, protocols, instructions, data, etc., on the clinical use of the equipment.
35. Quality controlEssential to measure performance of equipment consistent within accepted tolerancesA QC program of regular performance checks begins immediately after commissioning If QC measurements identify departures from expected performance, corrective actions are required.
36. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.3.2. Slide 4action level =2 x tolerance levelmeanvaluetolerance level equivalent to 95% confidence interval of uncertainty action level =2 x tolerance levelstandarduncertainty1 sd2 sd4 sdUncertainties, tolerances and action levels
37. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.3.7. Slide 2Steps of the treatment planning process, the professionals involved in each step and the QA activities associated with these steps (IAEA TRS 430) TPS related activityQA program for treatment planning systems
38. The computerized treatment planning system (TPS) is an essential tool in this process. Provides a computer based: simulation of the beam delivery set-upoptimization and prediction of the dose distributions to the target volume and to the normal tissues.Involves physicists, dosimetrists, RTTs, and radiation oncologists. Treatment planning QM needs a clear QA plan of the TPS and its use.
39. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.3.7. Slide 9 Acceptance Acceptance testsAcceptance testing resultsRTPSVENDORUSERQA program for treatment planning systems
40. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.3.7. Slide 10 Commissioning Commissioning proceduresCommissioning resultsPeriodic QA programRTPSUSER
41. QA program for treatment planning systems-referencesIAEA TRS 430 (2004)IAEA TecDoc 1540 (2007)AAPM Reports (TG-40 and TG-43), IPEM Reports 68 (1996) and 81 (1999), Van Dyk et al. (1993)
42. Patient chart reviewBasic components: patient name and ID, photograph, initial physical evaluation of the patient, treatment planning data, treatment execution data, clinical assessment during treatment, treatment summary and follow up, QA checklist. QA of the patient chart is essential.
43. All planning data as well as all data entered as the interface between the planning process and the treatment delivery process should be independently checkedExamples for that are:plan integritymonitor unit calculationsirradiation parameters. Data transferred automatically, e.g., from the treatment planning system, verified that no data corruption occurred. Patient charts
44. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.4.1. Slide 4All errors that are traced during chart checking must be thoroughly investigated and evaluated by the QA team The causes should be eradicated and may result in (written) changes in the various procedures of the treatment process. 12.4 TREATMENT DELIVERY 12.4.1 Patient charts
45. To verify field placement relative to anatomical structures for treatment.Beam aperture (blocks, MLC) properly produced and registeredPortal imaging
46. DRRs from treatment fields and large fields to verify the position of isocenter and the corresponding EPID fields.Comparison between digitally reconstructed radiographs (DRR) and EPIDDRR treatment fieldsDRR EPID fieldsEPID imagesPortal imaging
47. May lead to strategies for improvement of positioning accuracy such as:improvement of patient immobilization introduction of correction rules adjustment of margins in combination with dose escalationincorporation of set-up uncertainties in treatment planningPortal imaging
48. Review of Radiation Oncology Physics: A Handbook for Teachers and Students - 12.4.4. Slide 1Record-and-verify systemsCompare set-up parameters with the prescribed values and allow/prevent treatment.Patient ID, site, etcMachine parameters,Dose prescription and accumulated data. Tolerance tables specific to sites, etc.
49. National or international recommendations:World Health Organization (WHO)- 1988,AAPM - 1994, European Society for Therapeutic Radiation Oncology (ESTRO) -1995Clinical Oncology Information Network (COIN) - 1999 Recommendations for certain parts of the radiotherapy process:IEC - 1989 Institute of Physics and Engineering in Medicine (IPEM) - 1999. Where recommended standards are not available, local standards need to be developed, based on a local assessment of requirements.Quality standards in radiotherapy
50. Questions?Comments?