Quality Control and Quality Assurance: Radiation Oncology (Revised 12-12-19)

Revision History

The Quality Assurance Committee is responsible for establishing and reviewing clinical processes, and discussing process and clinical errors, establishing cause, effect, and solutions. In addition, the committee is responsible for reviewing/following up on:

• medical events

• machine down time

• percentage of weekly chart checks and EOT checks

• any treatment complications

• department clinical statistics (e.g., morbidity and mortality, outcome and focus studies, etc.)

• patient satisfaction surveys

• MD and Physicist peer review

• medical physicist QA reports

A formal physics policy and procedure manual should be in place and reviewed on an annual basis. A physics quality assurance (QA) manual is a set of policies and procedures describing all aspects of the radiation oncology physics program. The department should have a documented, formal treatment planning system QA plan, including the periodic confirmation of the treatment planning system’s consistency. The treatment planning system QA should be performed on an annual basis. Please refer to the report of the AAPM Radiation Therapy Committee Task Group 53 or AAPM Medical Physics Practice Guideline 5a for treatment planning system QA information.

Patient-specific QA for IMRT, SBRT, SRS, etc. should be documented and approved prior to initiation of treatment. It is recommended that the facility establish a standard for QA and set their pass/ fail criteria.

In addition, the following is required for radiation oncology QA/QC:

• A qualified medical physicist (QMP) must review each patient’s chart on a weekly basis. Chart checks by medical dosimetrists are not acceptable. Please reference ACR/AAPM Technical Standard for the Performance of Radiation Oncology Physics for External Beam Therapy (Section VI.C.3a).

• Policies and procedures should be established for high dose (> 300cGy/fraction) treatments. The physics manual should have a policy that specifically states that the plan/calculation will be checked prior to treatment; however, if your policy states that all plans and calculations must be reviewed prior to treatment, no additional policy is needed.

• At the completion of treatment, the QMP shall review the entire chart to affirm the fulfillment of the initial and/or revised prescription dose. This end of treatment (EOT) chart check should be documented by the physicist, initialed/signed and dated no later than one week after the end of treatment. An EOT chart check is a final review of all plans, calculations and patient dosimetry readings, weekly chart checks, etc.

• The prescription must be linked to an anatomical site and not just state PTV1, PTV2, and PTV3, for example, right upper lobe, left breast, etc. The point or volume that is being prescribed, for example, to 95% IDL or 95% volume should be included. A total cumulative dose should be entered in the prescription to indicate a dose beyond which they cannot treat.

• For periodic imaging QA, please refer to the report of the AAPM Radiation Therapy Committee Task Group 66 (AAPM TG-66). A QMP should perform an annual system dose check.

• For IMRT, SBRT, SRS, etc. treatment, heterogeneity correction should be used in treatment planning and its commissioning documented in a written report.

• AAPM TG-66 recommends an annual evaluation of the "electron density to CT number conversion" to be consistent with commissioning and manufacturer recommendations. There should be evidence of the implementation of this recommendation.

• Independent verification of output can be measured by TLD/OSL or by a separate independent medical physicist using their equipment.

• Brachytherapy radiation safety documentation must include at a minimum evidence of a post-procedure survey. Please refer to NRC regulations. Brachytherapy source calibration documentation must show that it was performed using an ADCL Well Chamber and the calibration check was done prior to source usage.

• An independent MU/backup calculation check program should be available.

• You will need at least one backup dosimetry system. You should have documentation that it has been intercompared periodically to the calibrated system.

• Hardware and software updates need to be documented.

• Thermometer and barometer comparison/calibration must be performed and documented annually, comparing these field instruments to a standard system.

• With regard to peer review of the medical physicist: for multi-physicist sites an annual evaluation or process must be checked by a different medical physicist who did not perform the original work; for solo-physicist sites please refer to AAPM TG 103.

A comprehensive review of the facility’s physics program will be included as part of the application process and verified during the on-site survey. The following areas will require documentation submitted with the application:

• Documentation of compliance with AAPM TG-51, TG-106, TG-119, TG-120, and TG-142

• Documentation of treatment planning system quality assurance program in accordance with TG-53 or relevant AAPM Medical Physics Practice Guideline

• Independent verification of output of each beam

In addition, during the on-site survey, the qualified medical physicist’s documentation of the following will be reviewed:

• Procedures for instrument calibration and periodic instrument constancy checks

• Procedures to verify the manufacturer’s specifications and to establish baseline performance values for radiation therapy equipment

• Quality management program for radiation therapy equipment, simulators, treatment planning systems, and monitor unit calculation algorithms

• Monitor units’ calculation procedures and protocols

• Physics chart check protocol for reviewing treatment delivery

• Procedures for checking the integrity of mechanical and electrical patient care devices

• Radiation protection program as it pertains to radiation oncology

• Calculations related to patient dosimetry and/or physics measurements when such needs arise or per clinician’s requests

For additional information regarding QA/QC for radiation oncology, please see the following:

• AAPM task group reports

• ACR/ASTRO Practice Parameters and ACR/AAPM Technical Standards

• AAPM medical physics practice guidelines

• ASTRO white papers

• QUANTEC

• NRC regulations

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