Patient transit and radiotherapy: Cost-effectiveness approach to environmental health savings.

e23146 Background: Environmental pollution and climate change exacerbate risks for cancer patients, potentiating carcinogenesis, respiratory illness, and cardiovascular disease. Hospital-sponsored patient transit presents an area to reduce healthcare’s emissions. Our recent study with Uber Health transitioning to electric [EV] or hybrid vehicles for patient radiotherapy (RT) transport achieved greenhouse gas (GHG) reductions without significantly increasing costs. 1 Clinically equivalent hypofractionated (HP) RT schedules (fewer, higher-dose sessions) may also reduce harmful emissions by 42–77%. 2 We use a cost-effectiveness framework to evaluate the combined impact of EV transit and HP RT on GHG-related health outcomes (disability-adjusted life-years [DALYs]) and transit costs. Methods: We analyzed 2024 Uber Health data from 5,063 rides (237 patients) to calculate transit costs for EVs and gas cars and roundtrip distances to RT (avg: 10.1 mi). 1 Using EPA/DOE emission factors for private vehicles (EV: 0.40, gas: 0.076 kgCO₂e/mi), we estimated GHG emissions per RT course. DALY losses from GHG emissions were calculated with validated conversion factors. 2 Scenarios were modeled for conventional (25 fractions (fx)), HP (15 fx), and ultra-HP (5 fx) RT schedules for breast cancer; incremental cost-effectiveness ratios (ICERs) represented ∆cost/∆DALY. Results: Interventions incorporating HP or ultra-HP for breast cancer were all cost-saving (Table 1). Switching to HP reduced transit-related costs by ~$400 per patient, and adding EV transit doubled DALY savings versus gas. Ultra-HP courses saved ~$800 per course, with EV transit increasing DALY savings by 20%. For conventional courses, EV (vs. gas) yielded an ICER of $5,384, demonstrating cost effectiveness under willingness-to-pay thresholds valuing a DALY at least $5,000. Conclusions: Integrating EV-based patient transit with HP RT may allow cancer care centers to minimize GHG-associated health risks while maximizing cost savings. This potentially scalable model aligns quality care and patient access with environmental stewardship and resource optimization. Future analyses should include patient/staff experiences and oncologic outcomes. References: 1. https://doi.org/10.1016/j.joclim.2023.100297 2. PMID: 38821084 Breast radiotherapy transit scenarios. Scenario ∆DALYs Saved ∆Cost ($) ICER* (∆cost/∆DALYs) Fuel varied (vs. gas); Fx constant (25) EV 0.00002600 $0.14 $5,385 Fx varied (vs. 25 fx); Fuel constant (gas) HP 0.00001284 -$396.78 -$30,901,869 Ultra-HP 0.00002568 -$793.55 -$30,901,480 Fuel (vs. gas) and Fx varied (vs. 25 fx) EV + HP 0.00002844 -$396.69 -$13,948,312 EV + Ultra-HP 0.00003088 -$793.53 -$25,697,215 *Negative ICER is cost-saving; positive ICER indicates increased cost to save DALYs. Non-GHG impacts (e.g. respiratory health effects) were not evaluated but may contribute significantly to DALYs lost .