In ovatingRadiation Oncology,Together 15-19 M ay2026 Stockholm ,Sweden Lorem Ipsum
Radiotherapy &Oncology Journal of the European SocieTy for Radiotherapy and Oncology
Volume 218 Supplement 1 (2026)
Radiotherapy & Oncology is available online: For ESTRO members: http://www.thegreenjournal.com For institutional libraries: http://www.sciencedirect.com
Editor-in-Chief
P. Blanchard
Amsterdam Boston London New York Oxford Paris Philadelphia San Diego St. Louis
International Standard Serial Number 0167-8140
© 2026 Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
This journal and the individual contributions contained in it are protected under copyright, and the following terms and conditions apply to their use in addition to the terms of any Creative Commons or other user license that has been applied by the publisher to an individual article: Photocopying Single photocopies of single articles may be made for personal use as allowed by national copyright laws. Permission is not required for photocopying of articles published under the CC BY license nor for photocopying for non-commercial purposes in accordance with any other user license applied by the publisher. Permission of the publisher and payment of a fee is required for all other photocopying, including multiple or systematic copying, copying for advertising or promotional purposes, resale, and all forms of document delivery. Special rates are available for educational institutions that wish to make photocopies for non-profit educational classroom use. Derivative Works Users may reproduce tables of contents or prepare lists of articles including abstracts for internal circulation within their institu- tions or companies. Other than for articles published under the CC BY license, permission of the publisher is required for resale or distribu tion outside the subscribing institution or company. For any subscribed articles or articles published under a CC BY-NC-ND license, permission of the publisher is required for all other derivative works, including compilations and translations. Storage or Usage Except as outlined above or as set out in the relevant user license, no part of this publication may be reproduced, stored in a retrieval sys- temor transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without prior written per- mission of the publisher. Permissions For information on how to seek permission visit www.elsevier.com/permissions Author rights Author(s) may have additional rights in their articles as set out in their agreement with the publisher (more information at http:// www.elsevier.com/authorsrights). Notice Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds or experiments described herein. Because of rapid advances in the medical sciences, in particular, independent verifica- tion of diagnoses and drug dosages should be made. To the fullest extent of the law, no responsibility is assumed by the publisher for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions or ideas contained in the material herein. Although all advertising material is expected to con- form to ethical (medical) standards, inclusion in this publication does not constitute a guarantee or endorsement of the quality or value of such product or of the claims made of it by its manufacturer
Orders, claims, and journal inquiries: Please visit our Support Hub page https://service.elsevier.com for assistance.
Funding Body Agreements and Policies Elsevier has established agreements and developed policies to allow authors whose articles appear in journals published by Elsevier, to comply with potential manuscript archiving requirements as specified as conditions of their grant awards. To learn more about existing agreements and policies please visit https://www.elsevier.com/fundingbodies
Available online at www.sciencedirect.com ScienceDirect
15-19 May 2026 Stockholm, Sweden
Table of contents
Abstract Reviewers Acknowledgement...............................................................................................................................1-3
BRACHYTHERAPY
Breast.................................................................................................................................................................................... 4-16 Gastro-intestinal, paediatric brachytherapy, miscellaneous.........................................................................................17-30 General brachytherapy.....................................................................................................................................................31-44 Gynaecology........................................................................................................................................................................4 -91 Head & neck, skin, eye....................................................................................................................................................92-110 Physics............................................................................................................................................................................ 111-149 Urology........................................................................................................................................................................... 150-179
CLINICAL
Biomarkers of clinical response...................................................................................................................................180-199 Breast.............................................................................................................................................................................. 200-352 CNS.................................................................................................................................................................................. 353-397 Gynaecological............................................................................................................................................................... 398-497 Haematology.................................................................................................................................................................. 498-527 Head & neck...................................................................................................................................................................528-676 Lower GI.........................................................................................................................................................................677-746 Lung................................................................................................................................................................................ 747-855 Mixed sites/palliation....................................................................................................................................................856-937 Non-malignant and functional radiotherapy..............................................................................................................938-961 Oligometastatic cancer.................................................................................................................................................962-997 Paediatric tumours......................................................................................................................................................998-1028 Sarcoma, skin cancer, malignant melanoma............................................................................................................102-1060 Upper GI.....................................................................................................................................................................1061-1126 Urology.......................................................................................................................................................................1127-1320
INTERDISCIPLNARY
Education in radiation oncology..............................................................................................................................1321-1350 Global health..............................................................................................................................................................1351-1376 Health economics & health services research........................................................................................................1377-1431 Other...........................................................................................................................................................................1432-1470 Patient involvement..................................................................................................................................................1471-1491 Public engagement and visibility of radiotherapy..................................................................................................1492-1498 Quality assurance and risk management...............................................................................................................1499-1542
PHYSICS
Autosegmentation.....................................................................................................................................................1543-1621 Detectors, dose measurement and phantoms......................................................................................................1622-1703 Dose prediction/calculation, optimisation and applications for particle therapy treatment planning............1704-1791 Dose prediction/calculation, optimisation and applications for photon and electron planning......................1792-2037 Image acquisition and processing...........................................................................................................................2038-2108 Inter-fraction motion management and daily adaptive radiotherapy.................................................................2109-2196 Intra-fraction motion management and real-time adaptive radiotherapy..........................................................2197-2278 Machine learning and AI algorithms........................................................................................................................2279-2320 Quality assurance and auditing...............................................................................................................................2321-2411 Radiomics, functional and biological imaging and outcome prediction..............................................................2412-2501
RADIOBIOLOGY
Biology of novel irradiation techniques..................................................................................................................2502-2514 DNA damage repair...................................................................................................................................................2515-2520 Immuno-radiobiology. ..............................................................................................................................................2521-2543 Microenvironment.....................................................................................................................................................2544-2557 Normal tissue radiobiology......................................................................................................................................2558-2589 Preclinical biomarkers...............................................................................................................................................2590-2597 Radiobiological modelling........................................................................................................................................2598-2609 Translational radiobiology........................................................................................................................................2610-2627 Tumour radiobiology................................................................................................................................................2628-2643
RTT
Patient experience and quality of life......................................................................................................................2644-2691 Patient preparation, immobilisation, and verification protocols ..........................................................................2692-2757 RTT contouring, target definition, and treatment planning ..................................................................................2758-2808 RTT education, training, and advanced practice....................................................................................................2809-2897 RTT operational practice and workflow innovations . ............................................................................................2898-2956
Late-breaking.............................................................................................................................................................2957-2974
Invited speaker..........................................................................................................................................................2975-3052
ABSTRACT REVIEWERS ACKNOWLEDGEMENT
ESTRO would like to thank the many people who helped with the 2026 abstract selection process. All abstracts are peer-reviewed by our group of over 700 experts. We thank them for their time and invaluable contribution to making the scienti fi c programme a success. Abstract Reviewers Aaron Kent, Abel Cordoba, Abrahams Ocanto, Adam Chiche ł , Agata Rembielak, Ahmed Gawish, Aidan Leong, Aileen Du ff ton, Ajay Aggarwal, Alan Hounsell, Alan Mcwilliam, Alan Melcher, Alba Fiorentino, Alejandra Mendez Romero, Aleksey Moiseev, Alessandro Cicchetti, Alessandro Scaggion, Alessio Bruni, Alessio Giuseppe Morganti, Alex Stewart, Alexandra Taylor, Alexandru Dasu, Alfonso Gomez-Iturriaga, Alina Emiliana Sturdza, Alison Tree, Almudena Zapatero, Alonso La Rosa, Amanda Moreira, Amanda Webster, Amy Chadwick, Ana Cravo, Ana Luísa Soares, Ana Maria Barragan Montero, Ananya Choudhury, Andrada Turcas, Andrea Lastrucci, Andrea Slocker Escarpa, Andreas Osztavics, Andreas Rimner, Andreas Smolders, Andrew Gosling, Andrew Nisbet, Andrew Wallis, Ane Appelt, Angel Montero Luis, Angela Baker, Angela Davey, Angeles Rovirosa, Angelo Filippo Monti, Anita O'Donovan, Ann Henry, Ann Sardo, Anna Bruynzeel, Anna Wilkins, Anne Gasnier, Anne Kiltie, Anne-Laure Bulin, Annemarie Devine, Annett Linge, Anouk Trip, Anthony Chalmers, Anton Mans, Anton Rink, Antonella Fogliata, Antonella Soriani, Antonio Angrisani, Apolo Salgado, Apostolos Menegakis, Arjen Van Der Schaaf, Arnaud Beddok, Åsa Carlsson Tedgren, Asha Latha Devalla, Ashwini Budrukkar, Astrid Van Der Horst, Aswin Ho ff mann, Aude Vaandering, Ay ş e Sedef Köseer, Azadeh Abravan, Bálint Tamaskovics, Banu Atalar, Bárbara Barbosa, Barbara Jereczek-Fossa, Barbara Knäusl, Barbara Vanderstraeten, Bartek Tomasik, Bartosz B ą k, Ben Slotman, Berardino De Bari, Bernhard Rhein, Berthe Aleman, Bianca Hoeben, Bill Nailon, Birgitte O ff ersen, Bradley Pieters, Bradley Prestidge, Bram Van Asselen, Brenda Murphy, Brendan Mcclean, Brett Cox, Brian Winey, Brita Singers Sørensen, Bruno Fionda, Bülent Polat, Cai Cai, Calogero Casà, Camilla Kronborg, Camilla Stokkevåg, Carien Creutzberg, Carles Muñoz-Montplet, Carlo Cavedon, Carlo Greco, Carmen Rubio, Carolina De La Pinta, Carsten Brink, Carsten Nieder, Casper Beijst, Catherine Dejean, Cecile Wolfs, Cem Onal, Cemile Ceylan, Charles Fouillade, Charlotte Brouwer, Charlotte Coles, Charlotte Robert, Christian Fiandra, Christian Kirisits, Christian Richter, Christian Rønn Hansen, Christopher Deufel, Cihan Gani, Claire Poole, Claude Defez Line, Claudia Rübe, Claudio Fiorino, Claudio Votta, Claus Andersen, Claus Preibisch Behrens, Clemens Seidel, Co Schnell, Coen Hurkmans, Colin Niaudet, Conny Vrieling, Conor Mcgarry, Conrado Guerrero Quiles, Corrie Marijnen, Crister Ceberg, Cristina Gutierrez Miguelez, Csaba Polgar, Cynthia Aristei, Dan Murray, Daniel Portik, Daniel Zips, Daniela Lidia Sandu, Daniela Schmitt, Daniela Thorwarth, Danielle Eekers, Danielle Fairweather, David Eaton, David Pasquier, David Sarrut, Davide Giovanni Bosetti, Dawid Bodusz, Delphine Antoni, Denis Panizza, Diana Raquel Dias Domingues, Diana-Cristina Pop, Diego Jurado-Bruggeman, Dietmar Georg, Dirk De Ruysscher, Dirk Rades, Dirk Verellen, Dirk Vordermark, Dn Sharma, Dominic Leiser, Dominik Wawrzuta, Donato Pezzulla, Dorota Gabrys, Anna Kirby, Ben O'Leary, Deepak Gupta, Farhannah Aly, James Bedford, Navita Somaiah, Teresa Guerrero Urbano, Yolanda Surjan, Soumyajit Roy, Dylan Callens, Edmond Sterpin, Eduard Gershkevitsh, Eirik Malinen, Eleanor Cheadle, Elena Clerici, Elena Manea, Eliana La Rocca, Eliana Vasquez Osorio, Elisabetta Cagni, Elizabeth Barnes, Elizabeth Forde, Elizabeth Joyce, Elke Beyreuther, Emma-Jane White, Emmanouil Fokas, Enrico Clementel, Eric Lartigau, Erica Bennett, Erik Van Der Bijl, Erik Van Limbergen, Eugenia Moretti, Eva Onjukka, Eva Van Weerd, Eva Versteijne, Evaggelos Pantelis, Fabien Milliat, Fabio Ynoe De Moraes, Falk Roeder, Famke Schneiders, Fatjona Kraja, Felipe Calvo, Felipe Couñago, Felix Ehret, Fernanda Herrera, Fernanda Villegas Navarro, Fernando Pizarro, Ferran Guedea, Filipe Cidade De Moura, Filippo Alongi, Finbar Slevin, Florence Huguet, Florian Stieler, Frances Duane, Francesca Albertini, Francesca De Felice, Francesca Di Franco, Francesco Cellini, Francesco Cuccia, Francesco Fracchiolla, Francesco Marampon, Frank Verhaegen, Franziska Eckert, Gabriel Adrian, Gabriel Paiva Fonseca, Gabriella Macchia, Gemma Eminowicz, Geo ff Budgell, Geo ff Higgins, George Mikhaeel, Georgina Fröhlich, Georgios Kritselis, Gerard Morton, Gerben Borst, Gerry Hanna, Gert De Meerleer, Ghizela Ana Maria Salagean, Gian Carlo Mattiucci, Gian Marco Petrianni, Gijs Bol, Gilles Crehange, Giovanna Gagliardi, Gitte Fredberg Persson, Giulia Marvaso, Giulio Francolini, Giuseppe Facondo, Giuseppe Schettino, Gokhan Ozyigit, Gregory Smyth, Guhan Rangaswamy, Guillaume Landry, Gustavo Marta, Guus Grimbergen, György Kovács, Md, Phd, Hanna Rahbek Mortensen, Hans Eich, Harley Stephens, Hathal Haddad, Heidi Lyng, Helen Barnes, Helen Grimes, Helen Jones, Helen Mcnair, Henrike Westerveld, Hugo Palmans, Icro Meattini, Ielizaveta Gorodetska, Ina Jurgenliemk-Schulz, Ina Nilo, Ingrid Kristensen, Inigo Martinez, Ioan Flavius Coser, Irena Koniarová, Isabel Pires, Isabelle Barillot, Isacco Desideri, Ivan Vogelius, J.B. Van De Kamer, Jaap
Jaspers, Jacob Johansen, Jacob Lindegaard, Jamema Swamidas, James Bates, Jamie Mcclelland, Jan Bussink, Jan Kriz, Jan Lagendijk, Jan Peeken, Jan Theys, Jana Jaal, Janita Van Timmeren, Jan-Jakob Sonke, Jarad Martin, Jarkko Ojala, Jasper Nijkamp, Jayde Nartey, Jean-Emmanuel Bibault, Jean-Michel Hannoun-Levi, Jenna Dean, Jenneke Jacobs, Jennifer Dhont, Jens Overgaard, Jesper Grau Eriksen, Jia-Ling Ruan, Jiazhou Wang, Jo Mitchell, Joanna I ż ewska, Joanna Socha, Joep Stroom, Joerg Lehmann, Johan Menten, Johann Tang, Johannes A. Langendijk, Johannes Kaanders, Johannes Knoth, John Maduro, John Rodgers, John Ryan, Jon Cacicedo, Jonas Willmann, Jordi Saez, Jorgen Johansen, Jose Belderbos, Jose Luis Guinot, Jose Perez Calatayud, Josep Maria Borras, Juan Antonio Vera-Sánchez, Judit Boda-Heggemann, Judith Van Loon, Julia Murray, Juliette Thariat, Kai Borm, Kamalram Thippu Jayaprakash, Kari Tanderup, Karin Dieckmann, Karin Goudschaal, Karunakaran Balaji, Kasper Rouschop, Katrien Vandecasteele, Kelly Yoo, Kelvin Ng Wei Siang, Kent Mouw, Kenton Thompson, Kerstin Borgmann, Kevin Harrington, Kevin Martell, Kim Benstead, Kim Kampen, Kristin K, Kristo ff er Petersson, Krzysztof Bujko, Kynann Aninditha, Lamberto Widesott, Lara Barazzuol, Lara Best, Lars Murrer, Lars Ulrik Fokdal, Laura Cella, Laura Feighan, Laura Motisi, Laura Mullaney, Laura Patricia Kaplan, Laure Marignol, Laurent Marmy, Lena Specht, Letizia Deantonio, Li Tee Tan, Liesbeth Boersma, Lígia Rolo, Liliana Stolarczyk, Linda Rossi, Lionel Perrier, Lior Braunstein, Lisa Wiersema, Lisanne Van Dijk, Lisette Juul Sandt, Liv Bolstad Hysing, Lizza Hendriks, Lone Ho ff mann, Loredana Dinapoli, Lorenzo Livi, Lorenzo Placidi, Lotte Fog, Louise Murray, Louise Turtle, Luc Beaulieu, Luca Boldrini, Luca Nicosia, Luca Tagliaferri, Luciana Caravatta, Lucy Evans, Ludvig Muren, Ludwig Dubois, Ludwig Van Den Berghe, Luisa Vanesa Biolatti, Ł ukasz Kuncman, Lynsey Devlin, M Rossi, Maaike Milder, Maarten Dirkx, Maarten Lambrecht, Maciej H, Maeve Kearney, Magnus Dillon, Maia Topeshashvili, Mairead Daly, Maja Guberina, Malin Kügele, Mania Aspradakis, Marcel Van Vugt, Marcel Verheij, Marcelino Hermida-Lopez, Marcin Miszczyk, Marco Caetano, Marco D'Andrea, Marco Esposito, Marco Fusella, Marco Riboldi, Margit Valgma, Maria Antonietta Gambacorta, Maria Carmen De Santis, Maria Dimopoulos, Maria Do Carmo Lopes, Maria Hawkins, Maria Tolia, Mariami Tchiabrishvili, Mariangela Massaccesi, Marianne Aznar, Marianne Falk, Marianne Koritzinsky, Marianne Nordsmark, Marie-Catherine Vozenin, Marina Khan, Mario Levis, Mario Terlizzi, Marion Essers, Marisol De Brabandere, Marjolein Van Os, Mark Hill, Mark Gooding, Mark Warren, Markus Alber, Markus Stock, Marta Capala, Marta Gimeno Morales, Martijn Intven, Martijn Kamphuis, Martin Fast, Mateusz Bilski, Mateusz Spa ł ek, Matteo Maspero, Max Schmid, Maximilian Deng, Maximilian Niyazi, Mechthild Krause, Meegan Shepherd, Mehmet Sen, Melek Tugce Yilmaz, Melissa Christiaens, Meredith Giuliani, Mererid Evans, Michael Fix, Michael Velec, Micha ł Posiewnik, Michela Buglione, Michele Fiore, Michelle Leech, Miguel A. Palacios, Mihaela Dumitru, Mikko Tenhunen, Min Ku, Mirjam Mast, Mischa Hoogeman, Mohammad Alfayez, Mohammad Hussein, Mohsen Bakhshandeh, Monica Mangoni, Morten Hoyer, Ben Heijmen, Tom Marchant, Aoife Williamson, Joanna Mcnamara, Napapat Amornwichet, Neil Richmond, Nejla Fourati, Nick Reynaert, Nicola Dinapoli, Nicolas Martz, Nicolaus Andratschke, Nienke Sijtsema, Nigel Anderson, Niluja Thiru, Nisha Shari ff , Nuradh Joseph, Nuria Jornet, Nuyts Sandra, Oliver Ott, Oliver Riesterer, Orit Person, Orla Mckivitt, Panagiotis Balermpas, Panagiotis Papagiannis, Pantelis Karaiskos, Paola Jablonska, Patrick Berkovic, Patrik Brodin, Patrizia Cornacchione, Paul Hill, Paul Sargos, Pawe ł Kuko ł owicz, Pedro Fernandes, Pedro Lara, Pedro Meireles, Per Munck af Rosenschöld, Per Poulsen, Periklis Papavasileiou, Pernille Lassen, Pervin Hurmuz, Peter Bownes, Peter Hoskin, Peter Nagle, Peter Nieho ff , Peter Orio, Peter Van Luijk, Peter Van Rossum, Philip Mayles, Philip Poortmans, Philipp Scherer, Pia Krause Møller, Pierina Navarria, Pierluigi Bonomo, Pierre Montay-Gruel, Piet Dirix, Piet Ost, Pinelopi Gkogkou, Piotr Wojcieszek, Pola Platoni, Prakash Umbarkar, Arthur Sun Myint, Frank Van Den Heuvel, Beate Timmermann, Heinz Schmidberger, Peter Greer, Puma Sundaresan, Rachel Brooks-Pearson, Rafal Dziadziuszko, Rainer Fietkau, Randi Syljuåsen, Raphael Bodensohn, Raphaël Moeckli, Rebecca Muirhead, Rémy Kinj, Richard Canters, Richard Poetter, Rick Haas, Rick Keesman, Riham Hany Medhat Abdelaziz, Rob Coppes, Rob Glynne- Jones, Rob Tijssen, Roger Taylor, Ruggero Spoto, Ruth Rodríguez Romero, Sabina Khan, Sagar Raut, Samantha Dicuonzo, Samantha Warren, Sandra Turner, Sanne Conijn, Sara Faithfull, Sara Ramella, Sarah Belhomme, Sarah Gulliford, Sarah Misson, Sarah Osman, Savino Cilla, Sebastiaan Breedveld, Sebastian Christ, Sebastian Klüter, Serenella Russo, Sergi Benavente, Seyed Alireza Javadinia, Shane Harding, Sharon Wong, Shoon Mya Aye, Silke Tribius, Silvia Chiesa, Simeon Nill, Simon Duke, Simon Rit, Simon Spohn, Simone Baroni, Siret Kivistik, Siyer Roohani, Slavka Lukacova, So fi a Rivera, So fi a Spampinato, Sona Michlikova, Sonja Wegener, Sophie Alexander, Sophie Boisbouvier, Sophie Espenel, Sophie Perryck, Stefania Pallotta, Stefania Volpe, Stefanie Corradini, Stefano Arcangeli, Stefano Leva, Stefano Lorentini, Stefano Maria Magrini, Stefano Vagge, Stella Kibena, Stephane Dufreneix, Stephanie Tanadini-Lang, Steven Habraken, Steven Petit, Stijn Van De Schoot, Sudesh Deshpande,
Supriya Chopra, Suraiya Dubash, Suresh Senan, Sushil Beriwal, Suzanne Van Beek, Syadwa Abdul Shukor, Tara Rosewall, Taran Paulsen Hellebust, Teodor Zah, Theresa O Donovan, Thomas Brunner, Thomas Lacornerie, Thomas Zilli, Tiago Ventura, Tibor Major, Till Böhlen, Tiuri Kroese, Tiziana Rancati, Tom Depuydt, Tomas Janssen, Tomas Kazda, Tomas Kron, Tomas Merino, Tonnis Nuver, Tord Hompland, Turid Hellevik, Umberto Ricardi, Ursula Nestle, Usman Lula, Uulke Van Der Heide, Vachaspati Kumar Mishra, Valeria Dionisi, Valerio Nardone, Valerio Pisoni, Vanessa Panettieri, Vania Batista, Vassilis Kouloulias, Vedrana Hertl, Vérane Achard, Véronique Vendrely, Vicki Taasti, Victor González Pérez, Victor Hernandez, Vincent Gregoire, Vincenzo Valentini, Vladimir Stserbakov, Vlatko Potkrajcic, Vratislav Strnad, Warren Bacorro, Wilma Heemsbergen, Winnie Li, Wolfgang Tomé, Wouter Crijns, Wouter Van Elmpt, Xavier Maldonado, Xuanfeng Ding, Yaacov Lawrence, Yasuo Yoshioka, Yat Man Tsang, Yavuz Anacak, Yazid Belkacemi, Yolande Lievens, Youlia Kirova, Yuen Nee Yvonne Loh, Yvette Seppenwoolde, Yvette Van Der Linden, Zineb Dahbi, Zoltan Takacsi-Nagy
BRACHYTHERAPY Breast
S5
Track-Topic
ESTRO 2026
95], respectively. Although DFS (92% vs 88%, p=0.03) and OS (91% vs 94%, p=0.02) slightly favoured the ≥ 2- day regimen, outcomes were comparable between single-day and multi-day schedules regarding 5-y LRCI and CSS (2% and 98% in both groups). Similar results were observed when comparing number of fractions. Late toxicity was observed in 189 patients (33%), with a total of 236 events. Grade 2 and 3 late toxicities represented 15.7% and 0.4% of cases, respectively, with no grade 4 events. The most frequent toxicities were fibrosis (61%), dyschromia (20%), and pain (15%). Rates of G ≥ 2 late events were not influenced by the treatment schedule (1 day: 8.6% vs ≥ 2 days: 9.2%, p=0.80), but were significantly higher for CTV >50 cc (p=0.001). Conclusion: VAPBI delivered with MIB in one to four fractions provides excellent 5-year local oncological outcome with minimal long-term toxicity. The treatment is feasible both in single-day and multi-day regimens, offering a safe, effective, and time-sparing de- escalation strategy for carefully selected patients with low-risk breast cancer. These mature results consolidate the role of vAPBI as a promising alternative to conventional whole-breast irradiation in modern breast-conserving therapy. References: VAPBI delivered with MIB in one to four fractions provides excellent 5-year local oncological outcome with minimal long-term toxicity. The treatment is feasible both in single-day and multi-day regimens, offering a safe, effective, and time-sparing de- escalation strategy for carefully selected patients with low-risk breast cancer. These mature results consolidate the role of vAPBI as a promising alternative to conventional whole-breast irradiation in modern breast-conserving therapy. Keywords: Breast cancer, brachytherapy, fractionation Single fraction based-very accelerated partial breast irradiation: 10-year results of the SiFEBI Phase 2 prospective trial Laura Haas 1,2 , Jocelyn Gal 3 , Mathieu Gauthier 1 , Renaud Schiappa 3 , Jean-Michel Hannoun-Levi 1 1 Radiation Oncology, Antoine Lacassagne Cancer Center, University Côte d’Azur, Nice, France. 2 Radiation Oncology, Henri Becquerel Cancer Center, Rouen, France. 3 Statistics, Antoine Lacassagne Cancer Center, University Côte d’Azur, Nice, France Purpose/Objective: This analysis updates the SiFEBI phase II trial (NCT01727011) evaluating very-accelerated partial Proffered Paper 557
Proffered Paper 218
Very accelerated partial breast irradiation in 1 or 2 days: Five-year oncological outcome of the GEC- ESTRO VAPBI cohort Jean-Michel Hannoun-Levi 1 , Cristina Gutierrez 2 , Marta Gimeno Morales 3 , Jocelyn Gal 4 , Javier Anchuelo 5 , Jose- Luis Guinot 6 , Miren Gaztañaga 7 , Norbert Meszaros 8 , Renaud Schiappa 4 , Vratislav Strnad 9 , Csaba Polgar 10 1 Radiation Oncology, Antoine Lacassagne Cancer Center, University Côte d’Azur, Nice, France. 2 Radiation Oncology, Institut Català d’Oncologia, Barcelona, Barcelona, Spain. 3 Radiation Oncology, Clínica Universidad de Navarra, Pamplona, Spain. 4 Statistics, Antoine Lacassagne Cancer Center – University of Côte d’Azur, Nice, France. 5 Radiation Oncology, Hospital Universitario Miguel Servet, Santander, Spain. 6 Radiation Oncology, Instituto Valenciano de Oncologia, Valencia, Spain. 7 Radiation Oncology, Hospital Clínico San Carlos, Madrid, Spain. 8 Radiation Oncology, National Institute of Oncology Budapest, Budapest, Hungary. 9 Radiation Oncology, Erlangen University Hospital, Erlangen, Germany. 10 Radiation Oncology, Semmelweis University, Budapest, Hungary Purpose/Objective: The aim of this updated analysis was to evaluate the long-term oncological outcomes of very accelerated partial breast irradiation (vAPBI) delivered with multicatheter interstitial brachytherapy (MIB) in patients with low-risk breast cancer. Material/Methods: This retrospective GEC-ESTRO observational international study (HDH F20220713143949) enrolled patients with early-stage low-risk breast cancer treated with lumpectomy followed by MIB-based vAPBI. Treatment regimens included one fraction (16–18Gy in 1 day), three fractions (3 × 7.45Gy over 2 days), or four fractions (4 × 6.2Gy over 2 days). Primary end point was oncological outcome including cumulative incidence of breast cancer local relapse (LRCI), regional relapse (RRCI) and metastatic relapse (MRCI) and disease-free (DFS), cause-specific (CSS) and overall (OS) survivals Secondary endpoints included late toxicity assessment. Results: Between 2012 and 2024, 579 patients were analysed. Median age was 72 years [40–101], median tumour size 12 mm [0.5–35]. Postoperative versus perioperative implantation was balanced (47.5% vs 52.5%). Treatment was delivered in 1 day in 37% (215 pts) and in ≥ 2 days in 63%. (3f: 220 pts; 4f: 144 pts). At a median follow-up of 64 months [62–67], 5-year oncological outcomes were excellent: LRCI 2% [1–3], RRCI 1% [0–1], and MRCI 1% [0–2]. Five-year DFS, SS, and OS were 91% [88–93], 98% [97–100], and 93% [90–
S6
Track-Topic
ESTRO 2026
Digital Poster 676
breast irradiation (vAPBI) delivered as a single fraction of postoperative multicatheter interstitial high-dose- rate brachytherapy (MIB) in elderly patients with low-
Impact of Applicator–OARs Distance on Dose Constraints in Accelerated Partial Breast Irradiation Using Strut-Adjusted Volume Implant (SAVI). Kauznori Miyaura 1,2 , Ryoichi Notake 3,2 , Hiroyuki Okamoto 4,2 , Ryoichi Yoshimura 5,2 1 Medical Physics Course, Graduate School of Health Sciences,, Showa medical university, Tokyo, Japan. 2 WASAVIs, Working group of APBI with SAVIs in Japan, Tokyo, Japan. 3 Radiology Center,, Tokyo Science University Hospital, Tokyo, Japan. 4 Radiation Safety and Quality Assurance Division, National Cancer Center Hospital, Tokyo, Japan. 5 Department of Radiation Therapeutics and Oncology, Tokyo Science University, Tokyo, Japan Purpose/Objective: Accelerated partial breast irradiation (APBI) using the Strut-Adjusted Volume Implant (SAVI) system allows conformal radiation delivery following breast- conserving surgery. However, the proximity of the applicator to organs at risk (OARs) such as the skin and chest wall can make it challenging to meet dose constraints. This study aimed to quantitatively evaluate the relationship between applicator–OAR distance and dose–volume parameters in APBI with SAVI, based on a multicenter observational dataset from the WASAVIs study in Japan (UMIN ID: 000021237). Material/Methods: Treatment planning data were collected in DICOM format (CT, structure, plan, and dose) from six institutions participating in the WASAVIs study. A total of 31 analyzable cases were included. On the planning CT images, the distances between SAVI and the skin (SAVI–SKIN) and between SAVI and the chest wall (SAVI–CHESTWALL) were measured at the slice where the applicator exhibited maximal expansion. Correlations were then analyzed between these distances and various dose–volume histogram (DVH) parameters, including PTV_EVAL V90%, V150%, V200%, SKIN D1cm3, and CHESTWALL D1cm3. The coefficient of determination (R2) from linear regression analysis was used to evaluate the strength of correlation. Results: The linear regression analysis demonstrated moderate correlations between applicator–OAR distance and OAR doses, with R2 values of approximately 0.5 for SKIN D1 cm3 and CHESTWALL D1 cm3. These findings suggest that shorter distances between the applicator and these OARs were associated with higher doses. In contrast, the correlation coefficients for PTV_EVAL V90%, V150%, and V200% were below 0.3, indicating that the applicator–OAR distance had a limited effect on target coverage parameters.
risk breast cancer. Material/Methods:
Patients aged ≥ 70 years (Balducci score I–II) with low- risk breast cancer (GEC-ESTRO classification) were enrolled in the SiFEBI trial. After lumpectomy, intraoperative catheter implantation was performed and postoperative vAPBI (single fraction, 16 Gy) was delivered. Surveillance occurred twice yearly. The primary endpoint was cumulative incidence of local recurrence rate (ciLR). Secondary endpoints included cumulative incidence of metastasis rate (ciMD), cancer- specific survival (CSS), overall survival (OS), late toxicity, and cosmetic outcome. Endocrine-therapy (ET) use and duration were also analysed; patients were considered adherent if they had taken ET for up to 50
months. Results:
From November 2012 to September 2014, 26 patients were enrolled. Median age was 76.6 years [69.4–88.9]. Median tumour size was 10.4 mm [4–17]. Histology was predominantly invasive ductal carcinoma (76.5%). Most tumours were low histologic grade (65%) and hormone-receptor positive (96%), All patients belonged to the luminal molecular subtype, with a median Ki-67 value of 10% [5–30]. Median surgical margins were 4 mm [2–10]. Median interval from surgery to vAPBI was 7 days [6–15]. After a median follow-up of 137 months [95%CI 134-147], the 10-year ciLR was 95% [95%CI 0.87-1]. Ten-year ciMD, CSS and OS rates were 0%, 100%, 81% [95%CI 67-97] respectively.Ten-year late toxicity occurred in 9 patients (34.6%), with a total of 9 events. Of these, 7 events (77.8%) were grade 1 and 2 (22.2%) were grade 2. Reported late effects included G2 breast pain in 1 pt (cytosteatonecrosis), G1 hypopigmentation in 3 pts, and breast fibrosis in 5 pts (G1: 4 pts; G2: 1 pt). Cosmetic outcomes were reported as excellent in 21 patients (81%) and good in 2 patients (8%).Median duration of ET was 59 months [3–61]. Twelve of 26 pts (46.2%) did not adhere to ET for up to 50 months including 1 pt who experienced local relapse 8 years after vAPBI. Conclusion: With 10 years of follow-up in this elderly, low-risk cohort, single-fraction postoperative MIB vAPBI (16 Gy) yielded excellent oncologic outcomes, notably high local control and cancer-specific survival. Late toxicity and cosmetic outcomes were acceptable. Further studies including larger cohorts with long follow-up would be valuable, particularly to allow meaningful comparison with ultra-hypofractionated external beam radiotherapy regimens. Keywords: Breast cancer, very APBI, single fraction
S7
Track-Topic
ESTRO 2026
Purpose/Objective: The risk of breast tumour recurrence following breast conserving surgery is highest around the index quadrant of the primary tumour. Partial breast irradiation is an option for women with early breast cancer. We report on a method of delivering partial breast irradiation using interstitial multicatheter high- dose-rate brachytherapy. Material/Methods: Women above the age of 50 years, with newly diagnosed unicentric invasive breast carcinoma measuring 3cm or less in maximal diameter, with negative surgical resection margins, were enrolled onto this single centre, single-arm, prospective trial. Exclusion criteria included lobular histology, lymphovascular invasion, HER-2 receptor positive tumours, hormone receptor negative tumours, axillary nodal involvement and metastatic disease. Enrolled patients underwent partial breast irradiation using interstitial multicatheter high-dose-rate brachytherapy to a dose of 34Gy in 10 fractions over one week. The post-surgical seroma cavity was identified on ultrasound imaging and catheters were implanted in multiple parallel planes under a general anaesthetic using the Elekta Breast CT/MR Template. Treatment planning was performed using Oncentra Brachy software. The primary outcome was the rate of ipsilateral breast tumour recurrences analysed in the as-treated population. Secondary outcomes were overall survival and progression free survival. Results: Between November 2011 and March 2021, 147 women were enrolled, and 144 received the intended treatment. Median age at date of enrolment was 62 years (range, 48-87 years). 135 patients (94%) had an Eastern Cooperative Oncology Group (ECOG) Performance Status of 0. 134 patients (93%) had stage pT1 tumours and 10 (7%) had stage pT2 tumours. The median primary tumour size was 10mm (range, 1.5- 26mm). The median PTV volume was 43.9cc (range, 8.3-131.6cc) and the median number of catheters implanted was 14 (range, 8-28). 6 patients (4%) received adjuvant chemotherapy, and 104 patients (72%) received adjuvant endocrine therapy. At a median follow-up 7.39 years, the 5-year and 7-year Kaplan-Meier estimated ipsilateral breast tumour recurrence rates were 2.1% (95% confidence interval [CI], 0.7-6.4%) and 3.3% (95% CI, 1.2-9.0%), respectively. The 5-year and 7-year estimated overall survival rates were 99.3% (95% CI, 94.9-99.9%) and 99.3% (95% CI, 94.9-99.9%), respectively. The 5-year and 7-year estimated progression-free survival rates were 94.3% (95% CI, 89.0-97.1%) and 92.2% (95% CI, 85.8-95.8%), respectively. Conclusion: Accelerated partial breast irradiation delivered using multicatheter high-dose-rate brachytherapy is an
Conclusion: This multicenter analysis revealed that the distance between the SAVI applicator and adjacent OARs significantly influences dose constraints in APBI. When the applicator is positioned close to the skin or chest wall, the corresponding OAR doses tend to increase, potentially complicating the achievement of clinically acceptable treatment plans. Although the impact on PTV_EVAL coverage was relatively minor, minimizing proximity to OARs during applicator placement may be crucial for optimizing dosimetric outcomes. These findings highlight the importance of pre-implant imaging assessment and careful applicator positioning to ensure both effective target coverage and OAR sparing in APBI using SAVI. Keywords: APBI, SAVI, References: Yoshida M. Yoshimura R. Notake R et al., Feasibility of accelerated partial breast irradiation with strut- adjusted volume implant brachytherapy in Japan focusing on dosimetry and acute toxicity: a Japanese multi-institutional prospective study. Breast cancer. 2024;31:75–83. Accelerated partial breast irradiation using interstitial multicatheter high-dose-rate brachytherapy: Efficacy results of a phase II prospective study George Cosman 1 , Lincoln Dinh 1 , Zoi Hei Wong 2 , Peter Graham 1 , Andrej Bece 1 , Gina Hesselberg 1 , Yaw Chin 1 1 Department of Radiation Oncology, St George Hospital, Sydney, Australia. 2 School of Medicine, University of New South Wales, Sydney, Australia Digital Poster 1472
S8
Track-Topic
ESTRO 2026
patients (100 %). Among those who underwent WBI, the cosmetic result was rated as ‘excellent’ by 63 out of 74 (85.2 %) surveyed patients (p = 0.003). Conclusion: In patients with early (T1-2N0M0) breast cancer APBI by high dose rate brachytherapy and WBI characterized by high efficacy with 97.7% and 98.3% local control with higher satisfaction of patients with cosmetic results after APBI. Keywords: APBI, early breast cancer, brachytherapy A novel form of breast IORT with CT-guided HDR brachytherapy: Final results of a prospective phase II clinical trial Lena M Turkheimer 1 , Gina R Petroni 2 , Melissa Lazar 3 , David R Brenin 1 , Anneke T Schroen 1 , Einsley M Janowski 4 , Bruce P Libby 5 , Timothy N Showalter 4 , Shayna L Showalter 1 1 Surgery, University of Virginia, Charlottesville, USA. 2 Public Health Sciences, University of Virginia, Charlottesville, USA. 3 Surgery, Thomas Jefferson Univeristy, Philadelphia, USA. 4 Radiation Oncology, University of Virginia, Charlottesville, USA. 5 Radiation Oncology, Moffitt Cancer Center, Tampa, USA Purpose/Objective: Conventional breast intraoperative radiation therapy (CB-IORT) delivers a single fraction of radiation during breast-conserving surgery (BCS), but lacks image Proffered Paper 1912 guidance and provides limited dosimetric optimization. Precision Breast IORT (PB-IORT) integrates intraoperative CT-based planning with high- dose-rate (HDR) brachytherapy, enabling individualized, image-guided radiation therapy. Following a Phase I feasibility study, this multicenter Phase II trial evaluated efficacy, toxicity, and cosmetic
effective alternative adjuvant radiation treatment for women with early breast cancer. Keywords: partial breast irradiation, multiplanar
Digital Poster 1702 Accelerated Partial Breast Irradiation: is it better than whole breast radiotherapy Sergey Nikolaevitch Novikov 1 , Bryantceva Zhanna 1 , Akulova Irina 1 , Melnik Julia 1 , Krivorotko Petr 2 , Ponomareva Olga 1 1 Radiotherapy, N.N. Petrov Cancer Institute, St Petersburg, Russian Federation. 2 Breast surgery, N.N. Petrov Cancer Institute, St Petersburg, Russian Federation Purpose/Objective: In single center prospective study to compare efficacy (five-year recurrence-free survival (RFS) and local control rate) and cosmetic results (according to self- assessment) of accelerated partial breast (APBI) or standard whole breast irradiation (WBI) in patients with early breast cancer (BC). Material/Methods: From 2016 to 2020, 208 women with pT1-2N0M0 BC underwent breast-conserving surgery and postoperative radiotherapy (RT). Of these patients, 87 underwent APBI, while another 121 were treated by WBI followed by an additional boost to the tumor bed in patients with triple negative or ERCBB2+ BC and in women younger than 45 y.o. APBI was performed by high dose-rate brachytherapy (64 patients) with 192Ir as 8 fractions of 4 Гр (2 fractions per day with at least 6hr interval) or by external beam radiotherapy (IMRT) as 5 fractions of 6 Gy once per day. WBI was delivered by tangential 6 MeV fields as 15 − 16 fractions of 2,66 Gy.A follow-up telephone survey assessing satisfaction with post-RT cosmetic outcomes was conducted with the 208 patients; 149 patients completed the BREAST- Q v2.0 questionnaire. Results: The median follow-up for the group that received APBI was 81 months [62; 88]. For the group of 121 patients who underwent WBI followed by additional irradiation of the tumor bed, the median follow-up was 64 months [54; 82]. Five-year local control rates in the ipsilateral breast were 97.7 % in the APBI group and 98.3 % in the WBI group (p = 0.95). Two local recurrences were detected in APBI group: one – on the border of irradiated volume, another – de novo BC of different subtype in another quadrant. Two local recurrences were revealed in WBI group: both close to the tumor bed. The five-year relapse free rates in the two groups were as follows: 93.8% after APBI and 95.9% after WBI (p = 0.52). The cosmetic results after APBI was rated as ‘excellent’ by all 75 evaluated
outcomes of PB-IORT. Material/Methods:
This multicenter Phase II trial enrolled women aged ≥ 45 years with clinical N0 invasive carcinoma (IDC) or DCIS ≤ 3 cm who underwent BCS from 2015 to 2022. After BCS, a multi-lumen catheter was placed, followed by intraoperative CT-guided HDR planning to deliver 12.5 Gy to the lumpectomy bed. The primary endpoint was 5-year index-quadrant tumor recurrence (IQTR). Secondary endpoints included locoregional and distant recurrence, overall survival, adverse events (AEs), cosmetic outcomes, and an exploratory comparison of pre- versus post-pathology treatment timing. Results: The final analysis cohort included 357 participants, with a median age of 63 and a median tumor size
S9
Track-Topic
ESTRO 2026
1 Radiation Oncology, Fundación IMOR-Atrys Health, Barcelona, Spain. 2 Breast Surgery, Unidad de Senologia Avanzada, Barcelona, Spain. 3 Physics and Radiation Protection, Fundación IMOR-Atrys Health, Barcelona, Spain. 4 Clinical Dosimetry, Fundación IMOR-Atrys Health, Barcelona, Spain. 5 Radiation Oncology, Instituto de Oncologia Avanzada-Atrys Health, Barcelona, Spain. 6 Nuclear Medicine, Hospital Universitario Sagrado Corazón, Barcelona, Spain. 7 Radiation Oncology, Hospital del Mar, Barcelona, Spain Purpose/Objective: The aim of this abstract is to compare the irradiated boost volumes with EBRT-VMAT boost and Targeted Intraoperative Radiotherapy (TARGIT) boost with the hypothesis that boosting with intraoperative radiotherapy immediately after lumpectomy reduces the irradiated breast volume. Material/Methods:
of 0.9 cm. Most tumors were IDC (63.6%) and ER- positive (93.8%). Median follow-up was 6.4 years (IQR: 5.0, 8.0). Most patients initiated endocrine therapy (78.0% of eligible). The estimated 5-year cumulative incidence of IQTR was 4.1% (90% CI 2.8-5.8%) (Figure), with a 5-year IQTR-free survival of 93.1%. Whether PB- IORT was delivered pre- or post-pathology [3.6% (90% CI, 2.0-6.0%) vs. 6.2% (90% CI, 2.5-12.9%), Gray’s p=0.65], the 5-year cumulative incidences of IQTR were comparable. Loco-regional and distant recurrence rates were 1.2% (90% CI, .5-2.5%) and 0.6% (90% CI, .2- 1.8%), respectively. Five-year overall survival was 97.2%; only 3 of 19 deaths were attributable to breast cancer. Toxicities were infrequent: 239 (67%) participants experienced any AE, but only 12 (3%) experienced grade 3 or 4 AEs. Most patients (91%) had good/excellent cosmesis at 2 years.
A comparative cohort trial was conducted tocomparethe boost volumes with EBRT
and intraoperativeradiotherapy. The study includes 85 patients non-suitable for APBI based on ASTRO and ESTRO criteria who underwent intraoperative radiotherapy as a boost prior to whole breast irradiation between 2014 and 2023.EBRT Boost Volume Definition: V95%: rim of tissue localized 15mm around the tumor edge plus a margin of 5mm that receives the 95% of prescribed dose (V95%) To create this volumen we include the GTV( lumpectomy cavity, clips and distortion zone) an expansion of 15mm minus the minimum reported free resection margin were added to create the CTV. The PTV is the CTV+5mm margin. An structure that encompasses the isodose of 95% was created V95%.(Figure 1).IORT Boost Volume Definition:V10mm: Rim of 1cm around the applicator, encompassing the area that receives the biological effective.To calculated the V10mm, the total volume including the applicator volume plus 10 mm marginwas obtained, then the applicator volume was subtracted from the total volume to obtain the irradiatedboost IORT volume V10mm (Figure 2).Descriptive statistical analysis was performed for both continuous and categorical variables.Normality of the continuous variables V95% and V10mm was assessed using the Kolmogorov-Smirnov test.Relationship between both variables was analyzed using Spearman and Kendall correlation coefficients.Comparison of medians was performed using the Wilcoxon signed-rank test for related samples. Results: VariableMeanMedianMinimunMaximumStandart DeviationV95%EBRT159,8cc149,8cc50,80cc324,70cc69, 97V10mm IORT 71,45cc
Conclusion: PB-IORT demonstrated durable local control, few high- grade toxicities, and excellent cosmesis. The 5-year IQTR estimate (4.1%) lies within the TARGIT-A trial’s reported confidence interval (3.3%; 95% CI, 2.1-5.1%), suggesting similar clinical outcomes while offering technical advantages of image guidance and optimized HDR dosimetry. The observed toxicity compares favorably to APBI trials. These long-term results support PB-IORT as an effective and safe approach for single-fraction radiation therapy after BCS in appropriately selected patients. Keywords: IORT, HDR brachytherapy, breast cancer
Digital Poster 1945
Comparative analysis of Radiotherapy boost volumes: Intraoperative vs External Beam Radiotherapy IVAN GARCIA ZAMORA 1 , Miguel Prats de Puig 2 , Benjamin Guix 1 , Maria Ulla Miravet 2 , Jesus Enrique Mar Silva 2 , Jose Ignacio Tello Luque 3 , David Gutierrez Roca 4 , Marco Panichi 5 , Miguel Alonso Becerra 5 , Alessio Rocchi 1 , Antonio Muñoz Garcia 6 , Manel Algara Lopez 7
S10
Track-Topic
ESTRO 2026
Material/Methods: The study was initiated in 2019 (NCT04293796). All 40 patients included in the study before the start of NAST underwent SPECT-CT with 99mTc-MIBI for visualisation of the primary tumour. In women that reach complete instrumental response VAB was performed to prove pCR. Finally pCR was diagnosed in 28 (70%) of enrolled 40 patients. Clips were placed in the primary tumor volume (PrTV) before NAST initiation and during the VAB. Patients with pCR (28 women) underwent whole- breast irradiation with a boost to the PrTV. High-dose rate brachytherapy (HDRB) was the primary technique for boost delivery. Before CT guided needle insertion all patients underwent pre-insertion CT with subsequent fusion with pre-NAST SPECT-CT. In the cases of concordant topography of the clips and primary tumor HDRB was initiated, if it was differences in the clips and tumor position we used alternative approaches. Results: A complete overlap between the PrTV on the pre- treatment CT and the clip location on the simulation CT was observed in 16 (57.1%) patients, while a partial mismatch was noted in 5 (17.9%). HDRB performed in 20 of these 21 patients and electron boost was delivered in one case because of the close position of PrTV to the skin. A marked discrepancy between the PrTV and clip topography on the fused images was found in 7 (25%) cases. Among these, clips were not detected on simulation CT in 3 (10.7%) patients. In 5 of these 7 patients, fused images revealed anatomical landmarks (scar, fibrosis) that can be used for gross tumor volume identification and navigation of the needles. Finally, HDRBT was successfully used for boost delivery in 25 (89.2%) of these 28 patients, while a photon boost was applied in another 2 (7.2%) cases, and an electron boost in one (3.6%) women. Local recurrence was diagnosed in 2 (7.2%) of the 28 patients with pCR (mean follow-up 30 months). In one case, the recurrence was located in a different quadrant than the PrTV, suggesting initial multicentric tumor growth. Conclusion: The combination of clips placed during vacuum assisted biopsy with the fusion of pre-NAST and simulation CT images is crucial for accurate boost delivery. Keywords: surgery deescalation, boost, breast cancer
64,66cc29,32cc114,14cc21,04Diference 88,35cc 85,14cc21,48cc210,56cc48,93Table 1. Descriptive statistical analysis for V95% and V10mm volumes Statistically significant correlation was identified between V95% and V10mm using Spearman’s rank correlation coefficient and Kendall’s tau test (p < 0.001). The Wilcoxon signed-rank test for paired samples demonstrated a statistically significant difference between the medians of the two volumes (p < 0.001). Conclusion: Comparative analysis revealed that the boost irradiated volume with EBRT was more than twice that ofthe boost irradiated volume with IORT, with the difference reaching statistical significance. These findings suggest a consistent volumetric relationship between both techniques, and a substantial reduction of the irradiated volume with IORT Keywords: Intraoperative Radiotherapy, boost volume. References: 1 Customized computed tomography-based boost volumes in breast-conserving therapy use of the three- dimensional histologic information for clinical target volume margins.Bianca Hambeukers, M.A.et al. J. Radiation Oncology Biol. Phys., Vol. 75, No. 3, pp. 757– 763, 20092.Volume matters: Breast induration is associated with irradiated breast volume in the Danish Breast Cancer Group phase III randomized Partial Breast Irradiation trial. Mette S. Thomsen et al Radiotherapy and Oncology 177 (2022) 231–2353. Long-term results of targeted Intraoperative Radiotherapy (target) boost during breast-conserving surgery. Jayant s. Vaidya et al. Int. J.. Radiation Oncology Biology.Phys., Vol. 81,Nº. 4 pp. 1091-1097, 2011 Digital Poster Highlight 1998 Strategy of high dose rate brachytherapy boost delivery in “surgery de-escalation” study. Sergey N Novikov 1 , Zhanna Bryantceva 1 , Irina Akulova 1 , Petr Krivorotko 2 , Nikolay Amirov 2 , Olga Ponomareva 1 , Sergey Kanaev 1 1 Radiotherapy, N.N. Petrov Cancer Institute, St Petersburg, Russian Federation. 2 breast surgery, N.N. Petrov Cancer Institute, St Petersburg, Russian Federation Purpose/Objective: To evaluate different approaches to target volume definition and technique of boost delivery in patients with a complete pathologic response (cPR) to neoadjuvant systemic therapy (NAST) who underwent radiotherapy with “surgery de-escalation” to vacuum- assisted breast (VAB) and sentinel lymph node biopsy.
Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12 Page 13 Page 14 Page 15 Page 16 Page 17 Page 18 Page 19 Page 20 Page 21 Page 22 Page 23 Page 24 Page 25 Page 26 Page 27 Page 28 Page 29 Page 30 Page 31 Page 32 Page 33 Page 34 Page 35 Page 36 Page 37 Page 38 Page 39 Page 40 Page 41 Page 42 Page 43 Page 44 Page 45 Page 46 Page 47 Page 48 Page 49 Page 50 Page 51 Page 52 Page 53 Page 54 Page 55 Page 56 Page 57 Page 58 Page 59 Page 60 Page 61 Page 62 Page 63 Page 64 Page 65 Page 66 Page 67 Page 68 Page 69 Page 70 Page 71 Page 72 Page 73 Page 74 Page 75 Page 76 Page 77 Page 78 Page 79 Page 80 Page 81 Page 82 Page 83 Page 84 Page 85 Page 86 Page 87 Page 88 Page 89 Page 90 Page 91 Page 92 Page 93 Page 94 Page 95 Page 96 Page 97 Page 98 Page 99 Page 100 Page 101 Page 102 Page 103 Page 104 Page 105 Page 106 Page 107 Page 108 Page 109 Page 110 Page 111 Page 112 Page 113 Page 114 Page 115 Page 116 Page 117 Page 118 Page 119 Page 120 Page 121 Page 122 Page 123 Page 124 Page 125 Page 126 Page 127 Page 128 Page 129 Page 130 Page 131 Page 132 Page 133 Page 134 Page 135 Page 136 Page 137 Page 138 Page 139 Page 140 Page 141 Page 142 Page 143 Page 144 Page 145 Page 146 Page 147 Page 148 Page 149 Page 150 Page 151 Page 152 Page 153 Page 154 Page 155 Page 156 Page 157 Page 158 Page 159 Page 160 Page 161 Page 162 Page 163 Page 164 Page 165 Page 166 Page 167 Page 168 Page 169 Page 170 Page 171 Page 172 Page 173 Page 174 Page 175 Page 176 Page 177 Page 178 Page 179 Page 180 Page 181 Page 182 Page 183 Page 184 Page 185 Page 186 Page 187 Page 188 Page 189 Page 190 Page 191 Page 192 Page 193 Page 194 Page 195 Page 196 Page 197 Page 198 Page 199 Page 200Made with FlippingBook - Share PDF online