Geographic Access to Radiation Therapy Services in Canada.

Abstract

The vast geography and sparse population of Canada pose substantial challenges to delivering radiation therapy services. In this cross-sectional study, we sought to characterize the geographic accessibility of radiation therapy in Canada and investigate where future radiation therapy facilities can be optimally located. Demographic and human geographic data were extracted from the 2021 Canadian Census for 57,937 dissemination areas (geographically stable regions of ∼400-700 persons), and active facilities providing megavoltage external beam radiation therapy were located using national and international directories. Logistic regression models were then used to analyze demographic factors associated with poor access to radiation therapy, defined as the absence of radiation therapy facilities within a 2-hour one-way driving radius. To inform planning efforts, we evaluated the impact of constructing a new radiation therapy facility in each dissemination area using multiple metrics of geographic access. The median driving time of the Canadian population to their nearest radiation therapy facility was 22.8 minutes. A total of 3,445,472 persons (9.3%) had poor access to radiation therapy in Canada, with significant variations by province (range, 3.3%-47.6%). Seniors aged ≥65 years, men, low-income individuals, internal migrants within Canada, and Indigenous people had higher odds of experiencing poor access to radiation therapy. In contrast, visible minorities, immigrants to Canada, and individuals with postsecondary education had lower odds of experiencing poor access. We identified eight locations across Canada where a new radiation therapy facility could achieve change-in-access metrics comparable or superior to those of recently opened facilities; establishing new facilities at all eight locations could reduce the population with poor access by 1,127,127 (32.7%). We found significant geographic and demographic disparities in access to radiation therapy across Canada. This study provides evidence that additional radiation therapy facilities are required to address existing inequities and better serve vulnerable populations, and the potential locations for new facilities that we identified can guide stakeholders in planning these expansions.