Clinical Trial Participation and Outcome for Patients with Glioblastoma: Multivariate Analysis from a Comprehensive Dataset

Glioblastoma multiforme (GBM) is the most common malignant brain tumor in adults. Although multiple clinical and tumor-related variables affect survival outcomes, the effect of clinical trial participation has not been explored. The aim of this study was to determine whether clinical trial participation improves outcome for patients with GBM. Data from patients with GBM were accessed from a dataset collected over 12 years (1998-2010) at two institutions. Univariable and multivariate logistic regression analyses were performed to look for relationships between clinical trial participation, other baseline clinical and sociodemographic variables and overall survival (OS). In total, 542 patients were identified and included in the analysis; median age was 62 years. Sixty-one patients (11%) were enrolled in a clinical trial. Clinical trial enrollment was associated with improved median survival (14.5 months compared to 6.3 months, p < 0.001) and this difference remained significant in multivariate analysis (hazard ratio 0.67, p = 0.046). Age, poor performance status and operation type were also independent predictors for OS in multivariate analysis. Disease site, socioeconomic status and co-morbidity did not affect survival outcome. This is the first study in patients with GBM to suggest a survival benefit from clinical trial participation, independent of age and performance status; while also confirming the importance of other previously reported prognostic factors. This should encourage clinicians to offer trial therapies to patients with GBM and encourage patients to participate in available studies.