P17.70 * CAN ELDERLY PATIENTS WITH GLIOBLASTOMA BENEFIT FROM CONVENTIONAL CHEMO-RADIOTHERAPY TREATMENT?
Authors: E. Pineda, I. Valduvieco, T. Pujol, L. Oleaga, T. Ribalta, L. Caral, J. Gonzalez, T. Boget, F. Graus, E. Verger
Journal: Neuro-Oncology (2014)

BACKGROUND: Glioblastoma (GBM) is the most life-threatening primary brain tumor, especially in elderly. Despite aggressive treatment, median survival among all GBM patients is only 12-15 months and is worse in elderly (6-9 months). The standard of care for elderly remains controversial. The purpose of this study is to assess the benefit of conventional treatment (Stupp regimen) in elderly patients. METHOD: We retrospectively reviewed a prospective database of 209 patients who were diagnosed with GBM at a single center from January 2005 to March 2013. All patients were divided into younger and elderly groups based on the cut-off age of 65 years. RESULTS: Of 209 patients diagnosed with GBM, 122 (58%) patients were younger than 65 years, and 87 (42%) patients were 65 years old or older. No differences were found in basal patient characteristics and neither in grade of resection between age subgroups. However elderly received less active treatment, radio-chemotherapy was less frequent in elderly (51% vs 73%) but radiotherapy alone (18% vs 8%) and non-oncological treatment after surgery was more frequent in elderly (31% vs 18%) (p = 0.002). No differences in median survival were found in elderly patients who received the same approach treatment than young patients. Median OS was 10.8 months in all GBM patients, 8.7 months in older and 13.6 months in younger patients (p = 0.019). Of all, 106 (51%) patients received Stupp regimen, 41 (47%) elderly and 65 (53%) young. Median OS in patients treated with conventional treatment was 18 months, without differences by age, 15.3 months in older and 18 months in younger (p = 0.228), neither differences were found in PFS (global of 8.2 months, 9.7 and 8.2 months, p = 0.307). MGMT status information was available only for 45.5% of patients that received Stupp regimen, 23 MGMT methylated, 25 MGMT unmethylated and 58 patients with MGMT not evaluable or not done. Surprisingly, no differences in OS were found between groups by MGMT status (19.2, 18.1 and 15.7 months respectively, p = 0.405). Significant differences in OS and post-progression survival (PPS) were found if patients received or not treatment at relapse (7.7 versus 20 months, p < 0.0001 and 1.7 versus 8.9 months, p < 0.0001). No differences between age subgroups in receiving it or not. Bevacizumab (BVZ) was the recurrence treatment in 60% of patients treated (31/52). PPS was better in patients treated with BVZ than in those treated with chemotherapy or surgery (12.4, 5.1 and 8.9 months, p < 0.0001). CONCLUSION: Elderly population newly diagnosed with GBM benefit from conventional treatment. Probably, undertreatment is the most important factor associated with poor survival in elderly newly diagnosed with GBM. Therefore, elderly patients should be encouraged to receive conventional active treatment. Recurrence treatment with bevacizumab might be an important factor in improving survival in the last few years.