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

Background: 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.

Methods: 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]).

Results: 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.

Conclusion: Q-TWiST analysis identified patient groups that would benefit from more aggressive therapy. Further investigation with patient-generated utilities is needed.

Figures

Figure 1

Standard Fractionation Radiotherapy (SFX) Partitioned Survival

Figure 2

Hyperfractionation Radiotherapy (HFX) Partitioned Survival

Figure 3

Accelerated Hyperfractionated Radiotherapy with Split (AHFXS) Partitioned Survival

Figure 4

Accelerated Fractionated Radiotherapy with Concomitant Boost (AFXC) Partitioned Survival

Figure 5. Hyperfractionated Radiotherapy (HFX) versus Standard Radiotherapy (SFX) Threshold Plot

This is a threshold analysis for determining utilities between Standard Radiotherapy (SFX) and Hyperfractionated Radiotherapy (HFX). Patients with a combination of utilities above the line would prefer HFX.

Figure 6. Accelerated Hyperfractionated Radiotherapy with Split versus Standard Fractionated Radiotherapy Threshold Plot

Threshold analysis comparing Accelerate Hyperfractionated radiotherapy with split (AHFXS) compared to standard radiotherapy (SFX). There is no combination of utilities that would result in AHFXS being superior to SFX.

Figure 7. Accelerated Fractionate Radiotherapy with Concomitant Boost versus Standard Fractionated Radiotherapy Threshold Plot

Threshold analysis comparing Accelerate Fractionated Radiotherapy with Concomitant boost (AFXC) compared to standard radiotherapy (SFX). There is no combination of utilities that would result in AFXC being superior to SFX.