TREATMENT, HEALTHCARE UTILIZATION AND OUTCOMES IN PATIENTS WITH GLIOBLASTOMA IN ONTARIO: A 10-YEAR COHORT STUDY

Glioblastoma (GBM) is the most common malignant primary brain tumour in adults. Receipt of adjuvant therapies has been shown to exert a significant positive effect on patient survival. Little is known however about how changes in standards of care and healthcare system factors, such as access, affect real-world outcomes. In this study, we provide an overview of GBM in Ontario and examine elements of care, including treatment patterns and healthcare utilization, from 2010-2019. Using linked health- administrative databases from Ontario, Canada, we conducted a population-based cohort study to examine the clinical and biological characteristics, treatment, and healthcare utilization patterns of adult GBM patients diagnosed between 2010-2019. The primary outcomes were enrollment in adjuvant chemoradiation treatment and 1-, 2-, and 5-year survival. All analyses were performed using the Statistical Analysis Software (SAS). 5392 patients were diagnosed with GBM in Ontario from 2010-2019 (58% male, 42% female). The median age at diagnosis was 64. Receipt of adjuvant chemoradiation within one year of diagnosis increased from 51% in 2010 to 63% in 2019. 1-year, 2-year, and 5-year overall survival plateaued, ranging between 40-43%, 15-19%, and 5-7%, respectively. For patients above the age of 65, however, 1-year survival increased from 19% in 2010 to 26% in 2019. This Ontario- based study provides insight into the effect of practice evolution and healthcare utilization on the real-world overall survival of patients with GBM. Overall survival for most patients with glioblastoma has remained stagnant over the past decade. Changes intreatment standards and expansion of access to treating centres have been associated with prolonged survival in elderly glioblastoma patients.