TH‐E‐500‐01: Formal Radiation Therapy Safety Processes
Authors: Huq MS , Pawlicki T , Sherouse G 
Published: July 2013

Modern radiation therapy has become increasingly complex. In order to maintain a high level of safety, medical physicists are shifting their approach to safety from historical to formal. Quality assurance (QA) is not a unique challenge to radiation therapy, let alone medicine. Every industry has an approach to measuring, maintaining, and ensuring quality. Industrial and professional standards provide benchmarks and guidelines for the type, frequency, and specifications for QA tests. In each case, domain‐specific expertise is required to design the QA processes and manage the information workflow. The radiation therapy workflow is not exceedingly complex, but it contains many human‐driven steps and interaction points and the errors can be catastrophic and systematic. In the past, the level of complexity was considered to be sufficiently low that the team members could themselves manage and conduct individual steps in the QA chain. This did not mean that the error rates were smaller in the past; a lack of comprehensive error reporting does not allow such an analysis. A review of limited error reporting data as well as anecdotal evidence indicates that errors occurred in at least as high a rate as they do now. Patient positioning errors, inaccurate calculations, errors in the use of ancillary devices, were too common and the rate of these errors has likely dropped due to a greater reliance on computers to plan and monitor treatments. If the increased complexity has not driven a reexamination of radiation therapy QA, it has been a catalyst for this change. For example, the computerization of the radiation therapy workflow has reduced the reliance on the therapist's selection of an interlocked accessory, but increased the reliance of the upstream correct selection of the accessory, as well as an unbroken chain in the information flow from planning to delivery. Another important contribution to the reexamination of the QA paradigm was the increased complexity in the treatment plan. Where once 3–4 block‐defined fields were utilized, there are now literally hundreds of dynamically delivered subfields, any of which would have been deemed unverifiable in the past. The goal of the formalization of radiation therapy QA, and more generally, quality management (QM), is to continue to improve the error rate while maintaining, or even improving the process speed, efficiency, and even efficacy. Formal QM programs, of which QA is a part, contain the following components: Safety culture, QA support, quality measurement and feedback cycles, continuous quality improvement, process control, education and training, and error management. This symposium will define these terms and introduce the radiation therapy medical physicist into the efforts by the AAPM and other organizations in formalizing the QM and QA workflows to continue to improve the radiation therapy safety record.Learning Objectives:1. Understand the need for formal QM and QA processes2. Understand formal QM and QA techniques3. Understand how formal QM and QA techniques are being applied to radiation therapy