ESTRO 2025 - Abstract Book

S1971

Clinical - Urology

ESTRO 2025

1699

Proffered Paper Long-term urinary continence and influencing factors after salvage radiotherapy: Results of the SAKK 0910 dose escalation trial Christina Schröder 1,2 , Daniel Rudolf Zwahlen 1 , Sämi Schär 3 , Tobias Hölscher 4 , Winfried Arnold 5 , Bülent Polat 6 , Guido Hildebrandt 7 , Arndt-Christian Müller 8 , Paul Martin Putora 9 , Alexandros Papachristofilou 10 , Corinne Schär 3 , Stefanie Hayoz 3 , Marcin Sumila 11 , Kathrin Zaugg 12 , Matthias Guckenberger 13 , Piet Ost 14 , Davide Giovanni Bosetti 15 , Christiane Reuter 16 , Silvia Gomez 12 , Kaouthar Khanfir 17 , Marcus Beck 18 , Oliver Riesterer 19 , George N. Thalmann 20 , Daniel M. Aebersold 21 , Pirus Ghadjar 18,2 1 Department of Radiation Oncology, Kantonsspital Winterthur, Winterthur, Switzerland. 2 Department of Radiation Oncology, Inselspital, Bern University Hospital, and Bern University, Bern, Switzerland. 3 Swiss Group for Clinical Cancer Research, Competence Center, Bern, Switzerland. 4 Department of Radiation Oncology, University Hospital Carl Gustav Carus, Technische Universität, Dresden, Dresden, Germany. 5 Department of Radiation Oncology, Kantonsspital Luzern, Lucerne, Switzerland. 6 Department of Radiation Oncology, University Hospital Würzburg, Würzburg, Germany. 7 Department of Radiation Oncology, University Hospital Rostock, Rostock, Germany. 8 Department of Radiation Oncology, University Hospital Tübingen, Tübingen, Germany. 9 Department of Radiation Oncology, Kantonsspital Sankt Gallen, Sankt Gallen, Switzerland. 10 Department of Radiation Oncology, University Hospital Basel, Basel, Switzerland. 11 Department of Radiation Oncology, Hirslanden Hospital Group, Zurich, Switzerland. 12 Department of Radiation Oncology, Stadtspital Triemli, Zurich, Switzerland. 13 Department of Radiation Oncology, University Hospital Zurich, Zurich, Switzerland. 14 Department of Radiation Oncology, Ghent University Hospital, Ghent, Belgium. 15 Department of Radiation Oncology, Oncology Institute of Southern Switzerland (IOSI), EOC, Bellinzona, Switzerland. 16 Department of Radiation Oncology, Kantonsspital Münsterlingen, Münsterlingen, Switzerland. 17 Department of Radiation Oncology, Hôpital du Valais, Sion, Switzerland. 18 Department of Radiation Oncology, Charité – Universitätsmedizin Berlin, Berlin, Germany. 19 Department of Radiation Oncology, Kantonsspital Aarau, Aarau, Switzerland. 20 Department of Urology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland. 21 Department of Radiation Oncology, Inselspital, Bern University Hospital, and Bern University,, Bern, Switzerland Purpose/Objective: Urinary incontinence (UI) is common after radical prostatectomy (RPE) and salvage radiotherapy (sRT). The effect of dose escalated sRT is unclear. This study aimed to investigate late UI after sRT and the effect of dose escalation on late UI, incontinence recovery, and quality of life (QoL) as part of the SAKK 0910 phase III trial. Material/Methods: The SAKK 0910 trial was a multicenter, randomized, controlled study comparing two RT doses (64Gy/32 fractions vs. 70Gy/35 fractions) in patients with biochemical recurrence of prostate cancer following RPE. Eligible patients were randomized to receive either conventional (64Gy) or escalated (70Gy) radiation. Baseline and follow-up data were collected on urinary incontinence, quality of life (QoL), and treatment toxicity using standardized criteria. Results: A total of 344 evaluable patients were analyzed. Of these 344 patients, 53.2% of patients received nerve-sparing RPE and 56.1% were treated using a IMRT/VMAT RT techniques. Baseline incontinence prior to sRT (≥Grade (G)1) was reported in 32.2% of patients in the overall cohort, with 8.7% having ≥G2. During follow-up, 110 (47.2%) of the initially continent (