Variation over time and interdependence between disease progression and death among patients with glioblastoma (GBM) on RTOG 0525.

2017 Background: We assessed the longitudinal hazard characteristics for death and progression in newly diagnosed GBM patients, evaluated the impact of prognostic factors and treatment on the hazard within different time intervals to determine if effects are time-variant, and quantified the prognostic influence of disease progression on survival. Methods: Among patients randomized to Radiation Therapy Oncology Group (RTOG) 0525 comparing dose-dense (dd) with standard dose (sd) temozolomide (TMZ), we estimated the death and failure (death or progression) hazards over time, compared the hazard difference between subgroups within time intervals, and assessed the effect of disease progression on survival. Results: In the entire group, the peak hazard of death occurred from 9 to 24 months with a slow decline after that; the average monthly hazards are 2.9%, 6.07%, and 3.71%, respectively for three intervals: prior to 9, 9-24 and after 24 months; the hazard of progression/death reached a peak around 6 months (i...