ESTRO 2025 - Abstract Book

S989

Clinical – Head & neck

ESTRO 2025

a pre-RT tooth count over or under 20 teeth and the presence of TMJ sounds, masticatory pain, mandibular deviation, headache, and bruxism.

Conclusion: This interim analysis indicates that some craniofacial structural features may be a relevant factor in predicting the severity of post-RT trismus. While intermaxillary divergence was not shown to be correlated with post-RT MIO reduction, a significant correlation was found between increased clockwise mandibular rotation and reduced post RT MIO. Further analysis will be provided at completed accrual of this international study.

Keywords: Trismus, Head&Neck, Radiotherapy

References: 1) Spahiu O, Grossi C, Cavallin C, Chiofalo V, Cuffini EM, Lo Zito B, Catena F, Tortarolo A, Levis M, Piancino MG, Ricardi U, Iorio GC. Definitive radiotherapy and trismus in HNC patients: A critical review. Crit Rev Oncol Hematol. 2024 Nov;203:104486. doi: 10.1016/j.critrevonc.2024.104486. Epub 2024 Aug 27. PMID: 39197668.

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Proffered Paper What is the impact of treatment de-escalation on quality of life in patients with T1-2 oropharyngeal cancer? A secondary analysis of the ORATOR trials Alexa Dang 1,2 , David A. Palma 2 , Anthony C. Nichols 3 , Andrew Warner 2 , Eric Tran 1 , Andrew Bayley 4,5 , Khalil Sultanem 6 , Hien Le 7 , Marc Gaudet 8,9 , Irene Karam 10,5 , Robyn Banerjee 11 , Todd Tenenholz 12 , Eric Winquist 13 , Christopher D. Goodman 2 1 Radiation Oncology, BC Cancer, Vancouver, Canada. 2 Radiation Oncology, Western University, London, Canada. 3 Otolaryngology – Head and Neck Surgery, Western University, London, Canada. 4 Radiation Oncology, University Health Network, Toronto, Canada. 5 Radiation Oncology, University of Toronto, Toronto, Canada. 6 Radiation Oncology, McGill University, Montreal, Canada. 7 Radiation Oncology, Royal Adelaide Hospital, Adelaide, Australia. 8 Radiation Oncology, University of Ottawa, Ottawa, Canada. 9 Radiation Oncology, The Ottawa Hospital, Ottawa, Canada. 10 Radiation Oncology, Odette Cancer Centre, Toronto, Canada. 11 Radiation Oncology, University of Calgary, Calgary, Canada. 12 Radiation Oncology, West Virginia University, Morgantown, USA. 13 Medical Oncology, Western University, London, Canada