Patient Selection and Outcomes in Reirradiation for Head and Neck Cancers: A Prospective Cohort Study

Aims: Reirradiation (re-RT) in head and neck cancers requires careful patient selection. This study aimed to identify factors influencing re-RT decisions, analyse survival outcomes, and evaluate toxicities. Materials and methods: From 2013 to 2017, 250 patients previously treated with radical RT for head and neck cancers were prospectively included. Exclusions were prior RT dose <50 Gy, distant metastasis or prior RT within six months. The median disease-free interval (DFI) was 45.5 months, with a median follow-up of 52 months. Factors affecting survival were analysed, comparing outcomes between re-RT recipients and non-recipients in a propensity score-matched cohort. Results: Among 250 patients, 177 (70.8%) were advised re-RT. Long DFI (67%) was the most common reason for re-RT, while significant late sequelae (49%) often led to denial. Advanced recurrence stage (HR 1.549, p = 0.04), non-surgical intervention (HR 3.455, p < 0.005), non-recipients of re-RT (HR 4.459, p < 0.005) and organ dysfunction (HR 2.187, p < 0.005) predicted worse survival. For 162 re-RT recipients vs. non-recipients, the 3-year locoregional control, event-free survival and OS were 56.1% vs. 39.9% (p = 0.002), 42.1% vs. 26.7% (p = 0.002), and 57.1% vs. 31.3% (p < 0.001), respectively. After propensity matching, the re-RT group showed better 3-year OS (48.8% vs. 31.3%, p = 0.04) despite increased toxicities. Conclusion: Effective patient selection is vital for successful re-RT. Surgery followed by adjuvant RT yields optimal outcomes. Despite technical advancements, managing toxicities remains challenging. These findings provide valuable insights for clinicians facing the complex decision of re-RT in head and neck cancer patients.