Association of Time Interval From Surgery to Postoperative Radiation Therapy With Survival for Patients With Head and Neck Cancer

Background and Objectives Oncologic effect of initiating postoperative radiotherapy (PORT) in adherance with the National Comprehensive Cancer Network Guidelines remains uncertain. This study aimed to reassess the impact of time of initiating PORT over 6 weeks on survival.Subjects and Method Patients were dichotomized into groups according to the time of initiation, those that initiated PORT ≤6 weeks and those that initiated PORT >6 weeks postoperatively. The Kaplan-Meier, univariate, and multivariate analyses were then conducted. Outcome measures were overall survival (OS) and progression-free survival (PFS).Results OS rates at 5 years for the group that initiated PORT ≤6 weeks and those that initiated PORT >6 weeks were 86.3% and 72.9%, respectively (log-rank p=0.26). PFS rates at 5 years for the group of PORT ≤6 and for the group of PORT >6 weeks were 65.6% and 65.9%, respectively (log-rank p=0.95).Conclusion In this study, there was no statistical difference in OS and PFS rate between groups that began initiation of PORT ≤6 and those that began >6 weeks. In the future, retrospective studies with more patients will be needed to further confirm our observation from this study.