Quality-adjusted survival analysis of Radiation Therapy Oncology Group (RTOG) 90-03: phase III randomized study comparing altered fractionation to standard fractionation radiotherapy for locally advanced head and neck squamous cell carcinoma.

Abstract

To evaluate quality-adjusted survival (QAS) of patients with locally advanced squamous cell carcinoma of the head and neck treated with 4 different radiation fractionation schedules. QAS was calculated using the quality-adjusted time without toxicity or relapse (Q-TWiST) methodology. Utilities (patient preferences for certain health states) were obtained by threshold analysis. Q-TWiST therefore equaled TWiST + ([weight for toxicity] x [time spent in toxicity]) + ([weight for relapse] x [time spent in relapse]). A statistically significant increase in QAS existed for patients treated with hyperfractionated radiotherapy compared with standard fractionated radiotherapy (SFX) with a toxicity utility > or = 0.57 and relapse utility < or = 0.72. No statistically significant difference was observed for patients treated with the other 2 fractionation schedules compared with SFX. Q-TWiST analysis identified patient groups that would benefit from more aggressive therapy. Further investigation with patient-generated utilities is needed.