Advancing global equity in cancer care: Comparative environmental impacts of radiotherapy in Brazil and the U.S.

1627 Background: Climate change poses a significant threat to global health, necessitating efforts to address the environmental impacts of oncology care, particularly in low- and middle-income countries (LMICs). Radiation therapy is a cornerstone of cancer treatment, yet its delivery often involves high energy consumption and resource use, contributing to environmental degradation and inequities in health outcomes. Despite these challenges, the environmental footprint of radiotherapy in the Global South remains largely unexplored. This study quantifies the environmental impacts of radiotherapy in Brazil, compares these findings to external beam radiation therapy (EBRT) delivery in the U.S., and explores how sustainable practices may promote equity by reducing operational costs and expanding access to radiation therapy in underserved regions. Methods: A life cycle assessment (LCA) of EBRT for ten cancer disease sites was conducted at a radiation oncology clinic (Vitta) in Brasília, Brazil, following ISO 14040 and 14044 standardized methodology. Data on medical supplies, equipment usage, building energy consumption, and staff and patient travel from 2018-2023 was analyzed to assess environmental impacts across nine categories, including greenhouse gas emissions, air pollution, and carcinogenic potential. These results were compared with a previously published LCA of EBRT across four U.S. healthcare centers. Results: Radiotherapy at Vitta had a lower environmental impact across all categories compared to U.S. centers. Transit-related emissions were the largest contributor at Vitta, though they remained lower than those in the U.S. due to shorter travel distances (median 15 miles/week by public transit at Vitta vs. 48–90 miles/week by car in the U.S.). Vitta’s reliance on hydroelectric energy eliminated emissions from building heating and reduced cooling-related emissions to 9.3% of the clinic’s total footprint, compared to 74.0% at U.S. sites using mixed-grid electricity and natural gas. However, impacts from medical supplies at Vitta were higher across all categories, reflecting opportunities for resource optimization. Conclusions: This study provides novel insights into the environmental impact of radiotherapy in an LMIC context, underscoring the importance of regional differences in care delivery. The reduced environmental footprint at Vitta highlights the value of sustainable practices, such as renewable energy and public transit, in mitigating the health sector’s climate impact while reducing operational costs. These findings support the development of adaptable, scalable models for global radiation oncology, particularly in publicly funded and rural clinics, to expand access and promote equity in cancer care. Future research should prioritize environmentally sustainable strategies that align with the unique needs of LMICs and underserved populations.