ESTRO 2025 - Abstract Book

S2061

Clinical - Urology

ESTRO 2025

Conclusion: Three of the 122 patients presented with G3 ureteral obstruction. In only 1 of these 3 patients the published D max and D 0.1cc dose constraints were exceeded. However, 29 ureters received a dose exceeding these constraints but didn't report G3 toxicity. These findings suggest that surgery and/or chemotherapy may play a role in causing a G3 ureteral obstruction.

Keywords: Constraint

References: 1. Timmerman RD. An overview of hypofractionation and introduction to this issue of. Seminars in Radiation Oncology. 2008;18:215-22. 2. Hanna GG, Murray L, Patel R, Jain S, Aitken KL, Franks KN, et al. UK Consensus on Normal Tissue Dose Constraints for Stereotactic Radiotherapy. Clin Oncol (R Coll Radiol). 2018;30:5-14.

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Digital Poster MRI Guided Dose Escalated Stereotactic Prostate Radiotherapy: Acute and long-term clinical outcomes of initial 100 patients. Hendrick Tan 1,2 , Amita Sen 3 , Maddison Picton 4 , Charles Tran 3 , Vikneswary Batumalai 3 , Hilary Bryne 3 , David Crawford 3 , Tania Twentyman 3 , Michael Jameson 3 , Farshad Kasraei 3 , Monique Heinke 3 , Ursela Jelen 3 , Valery Peng 3 , Tommy Liang 1 , Eugene Leong 1,2 , Kasri Rahim 1,2 , Tee Lim 1,2 , Jeremy de Leon 3 1 Radiation Oncology, Genesiscare, Perth, Australia. 2 Radiation Oncology, Fiona Stanley Hospital, Perth, Australia. 3 Radiation Oncology, Genesiscare, Sydney, Australia. 4 Radiation Oncology, Genessicare, Perth, Australia Purpose/Objective: Magnetic resonance-guided adaptive radiotherapy (MRgART) allows for the effective delivery of stereotactic ablative body radiotherapy (SABR) techniques while reducing dose to organs at risk (OAR) and improving toxicity outcomes [1]. There is evidence of improved prostate cancer outcomes with simultaneous integrated boost (SIB) of the dominant intraprostatic lesion (DiL) [2]. This study aimed to evaluate the feasibility of MRgART for dose escalated prostate SABR on MR-Linac and assess toxicity in treated patients.

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