ESTRO 2025 - Abstract Book

S3656

Physics - Quality assurance and auditing

ESTRO 2025

3008

Digital Poster Identifying high-risk components in online adaptive RT through a multi-centre FMEA to address clinical trial QA needs Sarah OS Osman 1,2 , Sophie Alexander 3 , Joe Berresford 4 , Margaret Bidmead 5 , Matt Bolt 6 , Frank Brewster 4 , Jayna Chauhan 7 , Patricia Diez 1 , Alex Dunlop 5 , Cynthia Eccles 8 , Ben George 9 , Siobhan Graham 10 , Trina Herbert 3 , Rachel Hollingdale 6 , Ghirmay Kidane 11 , Dualta Mcquaid 6 , Elizabeth Miles 1 , Adam Mitchell 5 , Miriam Rashid 6 , Michael Thomas 5 , Philip Wai 7 , Dom Withers 11 , Catharine H Clark 1,2,12 1 National Radiotherapy Trials Quality Assurance (RTTQA) Group, Mount Vernon Cancer Centre, Northwood, United Kingdom. 2 Department of Radiotherapy Physics, University College London Hospitals, London, United Kingdom. 3 The Institute of Cancer Research, The Royal Marsden NHS Foundation Trust, London, United Kingdom. 4 Christie Medical Physics and Engineering, The Christie NHS Foundation Trust, Manchester, United Kingdom. 5 Joint Department of Physics, Institute of Cancer Research and Royal Marsden Hospital, London, United Kingdom. 6 Department of Oncology, Royal Surrey County Hospital NHS Foundation Trust, Guildford, United Kingdom. 7 Oncology, GenesisCare, Guildford, United Kingdom. 8 Department of Radiotherapy, The Christie NHS Foundation Trust, Manchester, United Kingdom. 9 Oncology, GenesisCare, Oxford, United Kingdom. 10 Radiotherapy, Barking Havering and Redbridge University Hospitals NHS Trust, Romford, United Kingdom. 11 Radiotherapy Physics, Barking Havering and Redbridge University Hospitals NHS Trust, Romford, United Kingdom. 12 Metrology for Medical Physics Centre, National Physical Laboratory, Teddington, United Kingdom Purpose/Objective: The integration of online adaptive radiotherapy (oART) in multi-centre clinical trials presents unique challenges for trial QA due to variability in treatment delivery processes across institutions, changing roles and responsibilities, and the need for both classical and novel safety barriers. This prospective Failure Mode and Effects Analysis (FMEA), aims to establish a consensus on high-risk failure modes (FMs) to inform the development of oART specific trials QA methodologies. Material/Methods: Utilizing a FMEA approach, teams from five UK RT centres with oART platforms (Varian ETHOS (2 centres), Elekta Unity (2 centres), ViewRay System MRIdian (1 centre)) and the national trial QA group, identified potential oART specific FMs throughout the oART workflow, spanning patient suitability (3FMs), preparation (1), setup (4), imaging (2), adaptive contouring (5), planning (5), dose calculation (2), plan review (1), deliverability (1), data transfer (1) and treatment delivery (1). Each FM was scored for occurrence (O), severity (S), and detectability (D), with a risk priority number (RPN) calculated as (O*S*D), with likely affected number of fractions for each FM considered [1]. Consensus on scoring was achieved through a modified Delphi approach, aligning participating centres on key safety priorities as defined in the AAPM Task Group 100 guidelines on risk-based QA [2]. Results: Twenty-six oART-specific FMs were identified for scoring (Figure 1). The highest scoring FMs from each centre were discussed among all participants. We identified that workflow plays an important role in a centre’s scores. Despite the wide range in RPN, ranking of FMs was generally consistent between centres. The 5 highest risk FMs included (2/5) contouring, (2/5) plan quality and (1/2) imaging FMs (Table 1).