QOL-23. Patient Reported Outcome Measures and Quality of Life from a randomized clinical trial for hypofractionated versus normofractionated chemoradiation for glioblastoma

Abstract INTRODUCTION For patients with glioblastoma (GBM), preserving quality of life remains a critical concern alongside pursuing effective therapy. The standard of care is postoperative chemoradiation with temozolomide (PMID: 15758009). A previous single arm phase II study suggests that extreme hypofractionation (6Gyx6) may offer comparable survival to the standard 6-week-schedule with reduced treatment time and costs (PMID: 25107913). Shorter treatment duration may also improve health-related quality of life (HRQoL). Our phase III randomized clinical trial (also to be presented at SNO 2025) in newly diagnosed GBM patients compared hypofractionated radiotherapy (6Gy×6 in 2 weeks) to standard fractionation (2Gy×30 in 6 weeks). All patients had a Karnofsky performance status ≥70 and received concurrent treatment and adjuvant temozolomide for 6 months. As main result of the trial, we could not demonstrate non-inferiority of the experimental hypofractionation schedule, as this schedule resulted in inferior progression-free and overall survival. We now present the HRQoL data from this trial. METHODS A key secondary endpoint was HRQoL, assessed via EQ-5D, EORTC QLQ-C30 and QLQ-BN20 at baseline, 1 month, 3 months and every 3 months, up to 24 months after radiation or up to progression. Main analysis of these scales includes comparison of major subscales and overall scores at 6 months, time-to-deterioration and longitudinal modeling. RESULTS Enrollment was halted early, due to poor accrual (n=129 of planned 474, n=65 experimental arm, n=64 standard arm). Preliminary analyses suggest inferior HRQoL in the experimental arm in several domains at predefined timepoints, including motor dysfunction and communication deficits. Longitudinal analysis of HRQoL is ongoing and will be presented at the SNO 2025 conference. CONCLUSION In the treatment of newly diagnosed glioblastoma with temozolomide-based chemoradiation, hypofractionation using 6Gy times 6 is preliminarily associated with inferior HRQoL, which may be due to earlier progression, and/or increased reports of radionecrosis.