ESTRO 2025 - Abstract Book

S1061

Clinical – Head & neck

ESTRO 2025

Conclusion: This study, using the largest ORN dataset ever curated, provides key insights into risk factors influencing earlier onset of ORN. Our analysis showed timing distributions of ORN onset; however, due to the matched case-control cohort design of the PREDMORN dataset, we did not include censored cases, which limits interpretation. Future work will focus on population-based modelling of time to ORN to improve generalisability and provide realistic survival probabilities.

Keywords: osteoradionecrosis, time-to-event

References: 1. Frankart, A. J. et al. Osteoradionecrosis: Exposing the Evidence Not the Bone. Int. J. Radiat. Oncol. Biol. Phys. 2021, 109 (5), 1206–1218. https://doi.org/10.1016/j.ijrobp.2020.12.043 2. Humbert-Vidan L. et al. 2031: Multivariable analysis of mandibular osteoradionecrosis predictors: results from the PREDMORN study. Radiotherapy and Oncology, Volume 194, Supplement 1, 2024, Pages S1367-S1371, ISSN 0167 8140, https://doi.org/10.1016/S0167-8140(24)02322-3 3. Humbert-Vidan L. et al. Protocol Letter: A Multi-Institutional Retrospective Case-Control Cohort Investigating PREDiction Models for Mandibular OsteoRadioNecrosis in Head and Neck Cancer (PREDMORN). Radiother. Oncol. 2022, 176, 99–100. https://doi.org/10.1016/j.radonc.2022.09.014

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Mini-Oral High-dose hypofractionated radiotherapy for palliation or primary treatment in 944 head and neck cancer patients with poor performance status Jørgen Johansen 1 , Christian Maare 2 , Anita B Gothelf 3 , Maria Andersen 4 , Mohammad Farhadi 5 , Peter B Pedersen 1 , Kathrine Kristiansen 6 , Jens Overgaard 7 , Jesper G Eriksen 6,7 1 Department of Oncology, Odense University Hospital, Odense, Denmark. 2 Department of Oncology, Copenhagen University Hospital Herlev, Herlev, Denmark. 3 Department of Oncology, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark. 4 Department of Oncology, Aalborg University Hospital, Aalborg, Denmark. 5 Department of Oncology, Næstved Hospital, Næstved, Denmark. 6 Department of Oncology, Aarhus University Hospital, Aarhus, Denmark. 7 Department of Experimental Clinical Oncology, Aarhus University Hospital, Aarhus, Denmark