3683 - Comparison of Dose Escalation in Radiotherapy for the Management of Head and Neck Neoplasms: Analysis of Survival and Late Toxicity
Presenter(s)
V. Monjarás Embriz1, S. Gutierrez Torres Sr2, F. Maldonado3, J. Altamirano2, and J. M. Hernández Martínez2; 1Instituto Nacional de Cancerologia, Mexico City, EM, Mexico, 2Instituto Nacional de Cancerología, Mexico City, EM, Mexico, 3Sociedad Mexicana de Radioterapeutas (SOMERA), Mexico City, Mexico
Purpose/Objective(s): Altered fractionation protocols are a treatment strategy in radiotherapy for head and neck tumors. The prognosis of these patients is determined by clinical stage, initial treatment, and pathological risk factors. Chronic toxicities associated with treatment have been identified, affecting patients' quality of life in the medium and long term. To determine overall survival and frequency of late toxicity in patients treated with radiotherapy in a definitive and/or adjuvant setting, comparing different fractionation protocols considering dose escalation with a BED10 above >84Gy.
Materials/Methods: A retrospective, observational, descriptive, and analytical study was conducted. The clinical and pathological characteristics of patients, the fractionation schedules used for head and neck tumors (oral cavity, oropharynx, larynx, and hypopharynx) in definitive and adjuvant setting, and their relationship with oncological outcomes and associated late toxicity were evaluated.
Results: A total of 218 patients with head and neck cancer (sites: oral cavity, oropharynx, larynx, and hypopharynx) treated with radiotherapy using different fractionation schedules were identified. A dose-escalation cutoff was established at >84 Gy (BED a/ß= 10 Gy) with IMRT and VMAT techniques in SIB, analyzing a cohort treated between 2018 and 2022 in our institution. The median survival in the BED >84 Gy group was 32.3 months (16.8 – 47.9) and 64 months (29.2 – 98.9) in the BED <84 Gy group, respectively (p=0.023). Late complications were reported in 38 patients (17.4%) in the BED >84 Gy group (p<0.001), including gastrostomy tube dependence (5.9%), esophageal stenosis (4.5%), and osteoradionecrosis (5%). In the Cox regression analysis, no factors favoring dose escalation were identified.
Conclusion: The treatment of patients with head and neck cancer presents a challenge from surgical, systemic therapy, and radiotherapy perspectives, requiring careful consideration of multiple factors in decision-making. As no benefit was found in dose escalation with BED >84 Gy—given the observed reduction in overall survival and increased late toxicity—treatment regimens should adhere to a BED of 84 Gy or lower to prevent long-term complications that negatively impact quality of life.