Radiation Therapy Accessibility in Cambodia and Mongolia-Geospatial Modeling Analysis in Low- and Middle-Income Countries Within the Asia-Pacific Region.

Abstract

Cambodia and Mongolia, both low- and middle-income countries within the Asia-Pacific region, face significant challenges in geographic accessibility to radiation therapy facilities (RTFs). This study aimed to quantify the current accessibility of RTFs in Cambodia and Mongolia, evaluating the potential benefits and challenges of establishing RTFs in regional provinces. Population and RTF location data were sourced from online databases. Local radiation oncologists identified potential sites for future RTF development. Geographic accessibility was determined by Euclidean distances from province centroids to existing and proposed RTFs. Isochrone maps were generated to measure the percentage of the population residing within 2 hours of driving time to RTFs. In Cambodia, existing RTFs are centralized in Phnom Penh. With proposed developments in Siem Reap and Kampong Cham, the median Euclidean distance would decrease from 135 to 99 km. The Cambodian population within 2 hours of an RTF is projected to rise from 37% to 50%. The sole RTF in Mongolia is in Ulaanbaatar. A first regional RTF is planned in the Western regional province of Khovd. Three additional sites were modeled in Khangai, Central, and Eastern regions. The current median Euclidean distance of 439 km would decrease to 273 km with the planned RTF in Khovd and to 186 km with developments across all health regions. The Mongolian population within a 2-hour driving time would increase from a baseline of 55% to 56% with the development in Khovd, and to 63% if all regional RTFs were developed. Geospatial modeling demonstrated an improvement in geographic accessibility with proposed RTF development in regional areas. Improvements in driving time are more significant in Cambodia; however, this still leaves a large proportion of the population with unacceptable travel burden. This study demonstrates the utility and limitations of geospatial analysis in resource planning for Asia-Pacific region low- and middle-income countries and advocates for further research into the relationship between accessibility and oncological outcomes in such settings.