Gliosarcoma in septuagenarians and octogenarians: What is the impact of adjuvant chemoradiation?

The objective of our study is to determine the impact of adjuvant chemoradiation on overall survival (OS) for gliosarcoma in septuagenarians and octogenarians. Data were extracted from the National Cancer Data Base (NCDB). Chi-square test, Kaplan-Meier method, and Cox regression models were employed in SPSS 23.0 (Armonk, NY: IBM Corp.) for data analyses. 210 patients with gliosarcoma who underwent resection were identified. 168 (80.0%) patients received adjuvant chemoradiation, and 42 (20.0%) received adjuvant RT alone. Patients were more likely to receive adjuvant chemoradiation if they were male vs. female (85.3% vs. 71.6%, p=0.016). There was no significant difference in receipt of adjuvant therapy by year of diagnosis, age at diagnosis, race, Charlson/Deyo Score, treatment facility type, tumor size, or extent of surgery. Those who received adjuvant chemoradiation had significantly better one-year OS than those who received adjuvant radiation alone (35.3% vs. 16.2%, p<0.001). On subset analysis, this significant one-year OS benefit was observed in septuagenarians, those with Charlson/Deyo Score of 0, and in those with tumor size ≤5cm. On multivariate analysis, receipt of adjuvant chemoradiation and greater extent of resection were independent prognostic factors for improved OS. Our data suggests that adjuvant chemoradiation is an independent prognostic factor for improved OS in elderly patients with gliosarcoma, and the results of our study can serve as estimated benchmarks for outcome in this growing and important patient population. Its benefit, however, may be limited to septuagenarians and those with lower comorbidity burden.