Faculty of Radiation Oncology Position Paper on the use of Image–Guided Radiation Therapy

Abstract

The development of technology such as intensity-modulated radiotherapy (IMRT), volumetric arc therapy (VMAT) and stereotactic ablative body radiotherapy (SABR) has resulted in highly conformal radiotherapy treatments. While such technology has allowed for improved dose delivery, it has also meant that improved accuracy in the treatment room is required. Image-guided radiotherapy (IGRT), the use of imaging prior to or during treatment delivery, has been shown to improve the accuracy of treatment delivery and in some circumstances, clinical outcomes. Allied with the adoption of highly conformal treatments, there is a need for stringent quality assurance processes in a multidisciplinary environment. In 2015, the Royal Australian and New Zealand College of Radiologist (RANZCR) updated its position paper on IGRT. The draft document was distributed through the membership of the Faculty of Radiation Oncology (FRO) for review and the final version was endorsed by the board of FRO. This article describes issues that radiotherapy departments throughout Australia and New Zealand should consider. It outlines the role of IGRT and reviews current clinical evidence supporting the benefit of IGRT in genitourinary, head and neck, and lung cancers. It also highlights important international publications which provide guidance on implementation and quality assurances for IGRT. A set of key recommendations are provided to guide safe and effective IGRT implementation and practice in the Australian and New Zealander context.

National survey on image‐guided radiotherapy practice in New Zealand

“…Image-guided radiotherapy is the use of imaging just prior to or during treatment, which when acted upon, improves or verifies the accuracy and precision of RT. 3 It is a complex, multi-step process that requires as a minimum, the execution of a series of key foundational elements in order to achieve its clinical goals. There are now a number of published guidelines available that aim to provide guidance on the safe and effective implementation of IGRT including the White Paper from American Society for Radiation Oncology (ASTRO).…”

“…The high variability in technologies and resources contributes to the challenges of producing detailed consensus guidelines for IGRT practices. 3 Several surveys have shown an increased adoption of IGRT technologies across many countries. 7,[9][10][11] However, little is known about IGRT practices in New Zealand (NZ), as there has been no collection of such data carried out.…”

Effect of patient size on image quality in radiotherapy kV planar verification imaging: a phantom study

“…While doses from IGRT are very small in comparison with treatment doses, extra dose from imaging is not completely negligible and should follow the As Low As Reasonable Achievable (ALARA) principle. 27 Any radiotherapy imaging protocol should be developed within a multi-disciplinary team and in accordance with published guidelines 1,9 with imaging dose balanced against clinical benefit achieved from extra imaging and the risk of inducing second malignant neoplasms. 1 This study provides a simple measure that can be taken at CT simulation and incorporated into an image verification protocol for large patients.…”

“…Image verification and the use of image‐guided radiotherapy (IGRT) underpin treatment success . Cone‐beam computed tomography (CBCT) is one option for image verification, with implementation undergoing a surge in Australia and New Zealand.…”

“…Image verification and the use of image-guided radiotherapy (IGRT) underpin treatment success. 1 Conebeam computed tomography (CBCT) is one option for image verification, with implementation undergoing a surge in Australia and New Zealand. Recent 2015-2016 surveys show that CBCT was available in 97% of Australian departments 2 and in 86% of New Zealand departments 3 compared with 8% of departments in this region having CBCT just a decade ago.…”