1236 - Split-Course Hypofractionated Radiotherapy in Elderly Patients with Head and Neck Squamous Cell Carcinoma: A Single-Center Prospective Phase II study
Presenter(s)
J. X. Yang1, Y. Xu2, G. Shayan3, X. Chen2, X. Huang4, K. WANG Jr5, Y. Qu2, J. Wang2, R. Wu2, Y. Tao6, J. Yi2, and Y. Zhang2; 1Department of Radiation Oncology, National Cancer Center / National Clinical Research Center For Cancer / Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China, 2Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China, 3Department of Radiation Oncology, National Cancer Center / National Clinical Research Center For Cancer / Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China, Beijing, China, 4National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, --- Select One ---, China, 5chinese academy of medical sciences tumor hospital oncology institute, beijing, China, 6Gustave Roussy, Villejuif, France
Purpose/Objective(s): Elderly patients with locally advanced head and neck squamous cell carcinoma (HNSCC) often cannot tolerate standard chemoradiotherapy. Split-course hypofractionated radiotherapy (SCH-RT) has emerged as a practical alternative, yet prospective evidence remains limited. This single-center phase II study prospectively evaluated the efficacy and safety of SCH-RT in elderly patients deemed unsuitable for standard curative treatment.
Materials/Methods: Patients aged =75 years with stage II-IVA HNSCC were enrolled. All underwent a standardized geriatric assessment using the Charlson Comorbidity Index (CCI) and received SCH-RT (33 Gy/10 fractions to PGTV, 25 Gy/10 fractions to PTV1), with involved-field irradiation (IFI) in two hypofractionated courses separated by 1-2 week interval. The primary endpoint was 6-month progression-free survival (PFS). Secondary endpoints included 18-month PFS, locoregional control rate (LRC), overall survival (OS), objective response rate (ORR), and toxicity.
Results: Between January 2024 and August 2025, 23 patients completed the prescribed treatment. Median follow-up was 19.0 (range, 7.0-30.9) months. The ORR was 95.7%, including 34.8% complete responses and 60.9% partial responses. Median PFS was 12.9 months, with 6-month and 18-month PFS rates of 76.9% (95% CI: 61.0%-97.0%) and 33.9% (95% CI: 17.1%-67.0%), respectively. Median OS was 16.0 months, with 18-month OS rate of 47.7% (95% CI: 28.5%-79.9%). The 18-month LRC rate was 54.2% (95% CI: 33.1%-88.7%). Grade 3 acute toxicities occurred in 13 patients (56.5%), mostly mucositis (43.5%). No grade 4–5 toxicities were observed.
Conclusion: SCH-RT with IFI demonstrates clinically meaningful antitumor activity and manageable toxicity in elderly HNSCC patients who are unsuitable for standard treatment. These data support SCH-RT as a feasible treatment option in this underserved population.