ESTRO 2025 - Abstract Book

S1893

Clinical - Urology

ESTRO 2025

Figure 2. ROC curves of dosimetric variables

Conclusion: Our study provided a comprehensive analysis of the dosimetric correlates associated with acute and late GI and GU toxicity in prostate SABR using the most commonly employed 5-fraction dose-volume constraints and we underlined the critical role of moderate dose regions in both acute and late GI and GU toxicity. Prostate treatment plans should be rigorously evaluated, and moderate doses should be minimized. The HU protocol is an eligible choice for 5-fraction SABR plans. Additionally, caution is advised for prostate volumes exceeding 60 cc.

Keywords: Prostate cancer, SABR, dosimetry

References: 1. King CR, Freeman D, Kaplan I, Fuller D, Bolzicco G, Collins S, et al. Stereotactic body radiotherapy for localized prostate cancer: pooled analysis from a multi-institutional consortium of prospective phase II trials. Radiother Oncol. 2013;109(2):217-21. doi: 10.1016/j.radonc.2013.08.030. 2. Jackson WC, Silva J, Hartman HE, Dess RT, Kishan AU, Beeler WH, et al. Stereotactic Body Radiation Therapy for Localized Prostate Cancer: A Systematic Review and Meta-Analysis of Over 6,000 Patients Treated On Prospective Studies. Int J Radiat Oncol Biol Phys. 2019;104(4):778-89. doi: 10.1016/j.ijrobp.2019.03.051.

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Poster Discussion Concurrent chemoradiotherapy with Cisplatin and Gemcitabine in muscle-invasive bladder cancer: results of a prospective phase II trial (NCT01495676) Morgan Michalet 1 , Philippe Ronchin 2 , Thomas Reynaud 3 , Nicolas Demogeot 4 , Simon Thézenas 5 , Jean-Michel Hannoun-Lévi 6 , Naji Salem 7 , Magali Quivrin 8 , Catherine Durdux 9 , Nazim Khalladi 10 , David Azria 1 1 Radiation oncology, Institut du Cancer de Montpellier, Montpellier, France. 2 Radiation oncology, Centre Azuréen de Cancérologie, Mougins, France. 3 Radiation oncology, CHU Saint-Etienne, Saint-Etienne, France. 4 Radiation oncology, Institut de cancérologie de lorraine, Nancy, France. 5 Biométrie, Institut du Cancer de Montpellier, Montpellier, France. 6 Radiation oncology, Centre Antoine Lacassagne, Nice, France. 7 Radiation oncology, Institut Paoli Calmettes,