P14.30 Treatment outcomes of newly-diagnosed glioblastoma multiforme (GBM) by O6-methylguanine DNA methyltransferase promoter (MGMT) status: a multi-country study
Abstract INTRODUCTION This study evaluated the relationship of MGMT status with first-line (1L) treatment outcomes of patients with newly-diagnosed GBM in France, Germany, Italy, Spain, the UK (EU5), and Canada. MATERIALS AND METHODS Medical oncologists and neuro-oncologists across EU5 and Canada completed a point in time, cross-sectional survey for the next 8 GBM patients seen between May and July 2016 within EU5 and Canada. All results apart from time to progression (TTP) were presented for patients receiving 1L active drug treatment. TTP was calculated from initiation of 1L treatment to initiation of second-line treatment. Results presented are statistically significant (p<0.05) unless otherwise specified. Bases vary depending on data availability. RESULTS A total of 241 physicians reported on 1747 patients with GBM. 875 were receiving 1L active drug treatment at time of survey. Mean age was 59.7 years (median=61) and 34.6% were women. Mean life expectancy was 14.9 months (median=12) at diagnosis and mean TTP was 8.5 months (median=7.3). Surgery was performed in 62% of patients (n=546) prior to 1L drug treatment; 38% of patients (n=329) had no surgery. Patients with surgery had a higher life expectancy at diagnosis vs patients with no surgery prior to 1L (mean=16.4 vs 12.2 months; median=15.0 vs 12.0). Patients who received corticosteroids (n=524) vs no corticosteroids during radiotherapy (n=64) had a shorter life expectancy at diagnosis (mean=15.0 vs 16.8 months, p=0.07; median=12.5 vs 13.9) and were more likely to have 8 or more inpatient days due to GBM (21% vs 8%, p=0.07) in the last 3 months prior to the survey. 62% of patients (n=541) had an MGMT-status recorded (tested: methylated or unmethylated), and 38% (n=334) were untested/ awaiting results (untested) at 1L. MGMT-tested patients had better life expectancy at diagnosis (mean=16.1 vs 12.9 months; median=15.0 vs 12.0) and longer TTP (mean=8.9 vs 7.8 months; median=7.8 vs 6.4) than untested patients. Among MGMT-tested patients, 58% were methylated and 42% were unmethylated. Methylated patients had similar life expectancy at diagnosis (mean=15.9 vs 16.3 months, p=0.85; median=15.0 vs 15.0) and TTP (mean=9.0 vs 8.8 months, p=0.42; median=8.0 vs 7.5) as unmethylated patients. CONCLUSIONS This analysis provides valuable insights into the 1L treatment outcomes of GBM patients in EU5 and Canada. Patients who did not undergo surgery had worse treatment outcomes. Steroid use appears to be associated with worse outcomes and higher healthcare resource utilization. Patient treatment outcomes varied depending on whether they are MGMT tested.