ESTRO 2025 - Abstract Book

S943

Clinical – Head & neck

ESTRO 2025

Purpose/Objective: To evaluate treatment outcomes of patients with HNSCC with indication of definitive radiotherapy but deemed unfit by head and neck multidisciplinary tumour board for combined or more prolonged treatment. Material/Methods: Patients with oral cavity, oropharynx, larynx and hypopharynx SCC considered frail and elderly but suitable for definitive radiotherapy were treated with hypofractionated schedule of 55 Gy in 20 fractions in 4 weeks. Intention to treat retrospective analysis of treatment outcomes was performed. Patients were assessed for comorbidity by Charlson comorbidity index (CCI) and for frailty by Geriatric 8 screening tool (G8). Treatment outcomes, frailty and comorbidity prevalence in two age groups with cut-off age of 65-years were compared. Results: The total of 49 patients (median age 71 years, range 56-88 years, 71.4% ≥65-years) in stage II (16.3%), stage III (22.4%), stage IVA (53.1%) and stage IVB (8.2%) were treated between January 2016 and December 2022. Median ECOG PS was 2 (1-3), median CCI was 6 (3-12) and median G8 screening tool score was 9 (4 14.5). Radiotherapy course was not completed in 10.2% and prolonged by >5 days in 10.2%. The median follow-up of living patients was 36 months (range 15-60 months). Local and/or distant recurrence was identified in 32.7% and 5.8% respectively. Thirty patients died and HNSCC was the cause of death in 63.3%. Three-year overall survival (OS), in 38.7% with all NG tubes removed by 1 month post RT, and PEG tubes were present in 4, 2 and 1 patient at 3-, 6- and 12-months post treatment. Three-year OS was lower in <65-years than in ≥65-years group with marginal significance (19.0% vs. 49.9%, p=0.069). For LCR and CSS, age <65-years compared to ≥65-years was associated with worse outcomes (LCR 40.8% vs. 72.7%; p=0.013, CSS 26.5% vs. 63.9%, p=0.005). Mean G8 scores were 8.3 and 10.2 (p=0.024) in <65-years and in ≥65-years group what pointed to higher frailty prevalence in younger patients. Conclusion: Hypofractionated definitive radiotherapy was completed as planned in high proportion of frail and elderly patients with predominantly locally advanced HNSCC. Frailty but not higher age was the principal risk factor for worse treatment outcomes. cancer specific survival (CSS) and local control rates (LCR) were 41.2%, 53.5% and 63.3% respectively. Enteral tube feeding before or during radiotherapy was commenced Poster Discussion Impact on survival of deviations of stereotactic ablative radiotherapy quality in GORTEC 2014-04 IIR trial of oligometastatic HNSCC patients yann sayous 1 , pauline maury 1 , antoine falcoz 2 , ryan marnaoui 3 , dewi vernerey 2 , cedric loiseau 4 , nazim khalladi 5 , xu shan sun 6 , Juliette Thariat 5 1 radiophysics, gustave roussy, villejuif, France. 2 Methodological and Quality of Life in Oncology Unit, University Hospital of CHBM, besancon, France. 3 radiation oncology, university hospital, amiens, France. 4 radiophysics, centre francois baclesse, caen, France. 5 radiation oncology, centre francois baclesse, caen, France. 6 radiation oncology, University Hospital of CHBM, montbeliard, France Purpose/Objective: Stereotactic Ablative Radiotherapy (SABR) is increasingly used in oligometastases (oMets) to defer initiation or switch of systemic treatments. The GORTEC 2014-04 phase IIR study (NCT03070366) showed that SABR-alone is a reasonable & cost-saving alternative to chemotherapy-based strategies based on survival without definitive quality of life deterioration. We assessed whether SABR quality influenced survival based on expert-based individual case Keywords: hypofraction, frail, elderly 838