ESTRO 2025 - Abstract Book

S2824

Physics - Dose prediction, optimisation and applications of photon and electron planning

ESTRO 2025

2632

Digital Poster Developing a National Framework for the Medical Physics Management of Patients Receiving Re-irradiation in Radiotherapy in Ireland. Paul Hill 1 , Louise Fahy 2 , Conor Heeney 3 , Karl Jordan 4 , Colin Kelly 5 , Anne Marie Kennedy 6 , Cora Marshall 6 , Margaret Moore 2 , Paul Mulligan 7 , Alan Pembroke 8 , Eoin Toomey 9 , Anysja Zuchora 2 1 Medical Physics, Cork University Hospital, Cork, Ireland. 2 Medical Physics, University Hospital Galway, Galway, Ireland. 3 Medical Physics, Mater Private, Limerick, Ireland. 4 Medical Physics, St Vincent's Private Hospital, Dublin, Ireland. 5 Medical Physics, St Luke's Hospital, Dublin, Ireland. 6 Medical Physics, Beacon Hospital, Dublin, Ireland. 7 Medical Physics, Galway Clinic, Galway, Ireland. 8 Medical Physics, UPMC Whitfield Hospital, Waterford, Ireland. 9 Medical Physics, Bon Secours Radiotherapy, Cork, Ireland Purpose/Objective: The number of invasive cancers, excluding non-melanoma skin cancer, is expected to double in Ireland by 2045 (NCRI 2019). Of these, approximately 50% of patients will require radiation therapy as part of their treatment, in either a curative or palliative setting (Atun 2015). As patients live longer, the number receiving more than one course of radiation is also growing. The treatment of patients in this re-irradiation scenario is complex. The historical and new treatment plans need to be combined with consideration of radiobiological effects due to different fractionations and elapsed time. The availability of the treatment record information may vary from summary paper reports to full DICOM datasets containing images, structure sets, plans and dose information. Each patient requires treatment tailored to their own specific needs and requires close cooperation within the multidisciplinary team of Radiation Oncologists, Medical Physicists, Dosimetrists and Radiotherapists. Material/Methods: A subcommittee of the Irish Association of Physicists in Medicine (IAPM) Radiotherapy Special Interest Group (RT SIG) was established to develop a national framework to assist individual departments develop their own local procedures from a Medical Physics perspective. The group was comprised of physicists representing all radiotherapy departments, public and private, in Ireland. A series of meetings were held to gather international best practice from diverse sources including clinical experience, existing publications, online resources (ESTRO 2023) and professional discussions. Results: An IAPM publication, “Framework for the Medical Physics Management of patients receiving re-irradiation in Radiotherapy” has been developed and is available to members through the website (IAPM). This covers topics such as: literature review, data availability, dose accumulation, dose metrics, image registration, clinical pathway, plan optimisation, beam algorithms, multimodality considerations and paediatrics. This framework aims to gather national and international best practice on re-irradiation in one place so that departments can select how these can be combined to develop their own local procedures. Conclusion: The treatment of patients in a re-irradiation setting is complex and requires careful consideration of the present clinical needs and the historical treatment. A multi-institutional physics group has worked to bring together the best available Medical Physics practice in one publication, facilitating individual departments to tailor it their own needs.

Keywords: Re-irradiation, Treatment Planning

References: Atun R. et al 2015, “Expanding global access to radiotherapy”, Lancet Oncology 2015, 16 (10), 1183-1186. doi: 10.1016/S1470-2045(15)00222-3