ESTRO 2023 - Abstract Book

S332

Sunday 14 May 2023

ESTRO 2023

Conclusion Pts generally reported similar side effect profiles across treatment groups and fractionation cohorts. DART was well tolerated with no evidence of increased toxicity. OC-0432 Patterns of Recurrence & Outcomes in Bladder Cancer Treated with Radiotherapy & Radiosensitisation T. Lodhi 1 , Y.P. Song 1 , T. Elumalai 2 , A. Hudson 1 , J. Logue 1 , J. Wylie 1 , W. Croxford 1 , M. Serra 1 , A. Tran 1 , R. Conroy 1 , P. Hoskin 3 , A. Choudhury 4 1 The Christie NHS Foundation Trust, Manchester Academic Health Science Centre, Department of Clinical Oncology, Manchester, United Kingdom; 2 Cambridge University Hospitals NHS Foundation Trust, Department of Clinical Oncology, Cambridge, United Kingdom; 3 Cancer Centre, Mount Vernon Hospital; Manchester Cancer Research Centre, University of Manchester, Department of Clinical Oncology; Division of Cancer Science, London/ Manchester, United Kingdom; 4 The Christie NHS Foundation Trust, Manchester Academic Health Science Centre; Manchester Cancer Research Centre, University of Manchester, Department of Clinical Oncology; Division of Cancer Science, Manchester, United Kingdom Purpose or Objective Radiotherapy plays a central role in muscle-invasive bladder cancer (MIBC) when combined with radiosensitisation and is an established standard of care. Given the different modes of action of radiosensitisers, we hypothesised that patterns of recurrence might differ between GemX (weekly low-dose gemcitabine) and carbogen and nicotinamide (BCON). Materials and Methods With institutional approval, clinical, pathological, and treatment parameters were obtained for a retrospective cohort study of patients treated with BCON or GemX radiotherapy between 2017-2021 based on clinician preference. Clinician- reported toxicity was assessed using RTOG grading during radiotherapy, 6 weeks, and 12 months after. Cross-sectional