Regional Variability in Survival for Patients Diagnosed with Selected Central Nervous System Tumours in Canada

Canada's decentralized healthcare system may lead to regional disparities in survival among Canadians diagnosed with central nervous system (CNS) tumours. We identified 50,670 patients diagnosed with a first-ever primary CNS tumour between 2008 and 2017 with follow-up until 31 December 2017. We selected the four highest incidence histologies and used proportional hazard regression to estimate hazard ratios (HRs) for five regions (British Columbia, Prairie Provinces, Ontario, Atlantic Provinces and the Territories), adjusting for sex, tumour behaviour and patient age. Ontario had the best survival profile for all histologies investigated. The Atlantic Provinces had the highest HR for glioblastoma (HR = 1.26, 95% CI: 1.18-1.35) and malignant glioma not otherwise specified (NOS) (Overall: HR = 1.87, 95% CI:1.43-2.43; Pediatric population: HR = 2.86, 95% CI: 1.28-6.39). For meningioma, the Territories had the highest HR (HR = 2.44, 95% CI: 1.09-5.45) followed by the Prairie Provinces (HR = 1.52, 95% CI: 1.38-1.67). For malignant unclassified tumours, the highest HRs were in British Columbia (HR = 1.45, 95% CI: 1.22-1.71) and the Atlantic Provinces (HR = 1.40, 95% CI: 1.13-1.74). There are regional differences in the survival of CNS patients at the population level for all four specific histological types of CNS tumours investigated. Factors contributing to these observed regional survival differences are unknown and warrant further investigation.