ESTRO meets Asia 2024 - Abstract Book

S27

Invited Speaker

ESTRO meets Asia 2024

1 Australian Clinical Dosimetry Service, Australian Radiation Protection and Nuclear Safety Agency, Melbourne, Australia. 2 Medical Radiation Services, Australian Radiation Protection and Nuclear Safety Agency, Melbourne, Australia

Abstract

The Australian Clinical Dosimetry Service (ACDS) has operated within the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) since 2010. The ACDS was designed for the Australian Department of Health by ARPANSA, in consultation with the Radiation Oncology professions, to provide a quality improvement tool to ensure safe and accurate radiotherapy across Australia. With responsibility for the entirety of the country, and with the policy requirement of equity of access, the ACDS audits are provided for the same cost wherever the facility is located within Australia. ACDS audits have been available to New Zealand facilities since 2018 under the same service model. Over more than a decade, the ACDS multi-level audit process has developed from testing conformal treatments on conventional linacs to include modern techniques such as volume modulated arc therapy (VMAT) and stereotactic ablative techniques (SABR, cranial SRS), and specialty treatment machines such as TomoTherapy®, CyberKnife® and Gamma Knife®. The combined audit results are a powerful benchmarking tool for peer comparison. From its audit findings, the ACDS can demonstrate an increase in patient safety and risk mitigation as systemic errors in radiotherapy systems have been identified and corrected.

509

A virtual audit system for intensity-modulated radiation therapy credentialing in Japan Clinical Oncology Group clinical trials

Mitsuhiro Nakamura

Medical Physics, Kyoto University, Kyoto, Japan

Abstract

In recent years, advancements in radiation therapy techniques have led to the increased use of sophisticated methods such as stereotactic body radiotherapy and intensity-modulated radiation therapy (IMRT) in prospective clinical trials. As the number of institutions participating in these trials grows, maintaining consistent treatment quality, particularly for those involving radiation therapy, has become paramount. Accurate and consistent dosimetry is crucial for maximizing the knowledge derived from these trials, underscoring the importance of audits for participating institutions. There are three types of audits for IMRT dosimetry credentialing: on-site, postal, and virtual. During on-site audits, external auditors visit each institution to perform dosimetry credentialing using their ionization chamber, electrometer, films, and phantoms. This allows auditors to verify the measurement process, including the institutional dose calibration protocol, and discuss immediate results. However, on-site audits involve significant travel costs and extended working hours. Currently, postal audits are the most prevalent. In this approach, a phantom containing small dosimeters, such as radiophotoluminescent glass dosimeters, thermoluminescent dosimeters, and films, is sent to participating institutions. Local staff perform the necessary procedures and return the phantom to the auditors for analysis. This method is employed by the Japan Clinical Oncology Group (JCOG) and the Imaging and Radiation Oncology Core for