Trends in glioblastoma: outcomes over time and type of intervention: a systematic evidence based analysis.

Despite aggressive treatment with chemoradiotherapy and maximum surgical resection, survival in patients with glioblastoma (GBM) remains poor. Ongoing efforts are aiming to prolong the lifespan of these patients; however, disparities exist in reported survival values with lack of clear evidence that objectively examines GBM survival trends. We aim to describe the current status and advances in the survival of patients with GBM, by analyzing median overall survival through time and between treatment modalities.