ESTRO 2025 - Abstract Book

Brachytherapy - Gastro-intestinal, paediatric brachytherapy, miscellaneous

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ESTRO 2025

Conclusion: SCRT-CT with brachytherapy, despite being chosen for more advanced tumours, has significantly better rectal preservation rates compared to LCRT with brachytherapy.

Keywords: MR-brachytherapy, Rectal Cancer, TNT

References: 1. Gerard, J.-P. et al. (2023) ‘Neoadjuvant chemoradiotherapy with radiation dose escalation with contact X-ray brachytherapy boost or external beam radiotherapy boost for organ preservation in early CT2–CT3 rectal adenocarcinoma (opera): A phase 3, RCT, The Lancet Gastroenterology & Hepatology, 8(4), pp. 356–367. doi:10.1016/s2468-1253(22)00392-2. 2. Julio Garcia-Aguilar et al. Organ Preservation in Patients With Rectal Adenocarcinoma Treated With Total Neoadjuvant Therapy. JCO 40 , 2546-2556(2022). DOI:10.1200/JCO.22.00032 3. Van der Valk, Maxime J MAhlberg, Madeleine et al. The Lancet, Volume 391, Issue 10139, 2537 - 2545 4. Bahadoer, Renu et al. RAPIDO: a randomised, open-label, ph3 RCT. The Lancet Oncology, 22, Issue 1, 29 - 42

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Digital Poster Dosimetric analysis of interstitial HDR-Brachytherapy in organ-preserving multimodal therapy of pediatric bladder/prostate rhabdomyosarcoma (BP-RMS) David Baumann 1 , Andreas Schmidt 2 , Hathal Haddad 1 , Elgin Hoffmann 1 , Andreas Manger 3 , Cristian Urla 2 , Maximilian Niyazi 1 , Jörg Fuchs 2 , Ulf Lamprecht 1 , Franziska Eckert 1 , Frank Paulsen 1 1 Department of Radiation Oncology, University Hospital Tübingen, Tübingen, Germany. 2 Department of Pediatric Surgery and Pediatric Urology, University Hospital Tübingen, Tübingen, Germany. 3 Department of Anesthesiology and Intensive Care Medicine, University Hospital Tübingen, Tübingen, Germany Purpose/Objective: The standard therapy for BP-RMS is a combination of chemotherapy and local therapies consisting of surgery and/or irradiation. In recent years, an organ-preserving surgery followed by interstitial HDR-Brachytherapy (iBT) has