Using Life Cycle Assessment as a Tool to Evaluate the Environmental Impact of Radiation Oncology and Inform Treatment Decision-Making in Early-Stage Breast Cancer

Abstract

The effects of climate change negatively impact patient health and healthcare delivery across the cancer care continuum. Environmental impacts arising from radiation therapy (RT), as measured with formal life cycle assessment (LCA) methods, have not been reported to date. LCA is a standardized approach to systematically analyze the effects a product or process has on the environment by accounting for all its components and their life cycle. Here, we used LCA to compare the footprint of RT delivery among several environmental impact categories, including carbon (CO2) emissions, in early-stage breast cancer (ESBC) regimens with clinical equivalency. We used LCA methods to estimate the environmental footprint of ESBC treatments across 9 standard impact categories including greenhouse gases, ozone depletion, smog, carcinogenics, and respiratory effects, in a cohort of 50 patients receiving moderate hypofractionation (mod-hEBRT) to 42.4 Gy in 16 fractions (n = 25) and ultra-hypofractionation (ultra-hEBRT) to 26 Gy in 5 fractions (n = 25). We analyzed life-cycle emissions associated with patient and staff commute, RT quality assurance and set-up equipment, linear accelerator (LINAC) requirements, clinic supplies, and linen use. Facility emission estimates are underway. All calculations were done in SimaPro 9.4 using the ecoinvent 3.8 database and TRACI 2.1 impact assessment methods. Confidence intervals were calculated using stochastic computations. Total emissions associated with delivering a full course of mod-hEBRT versus ultra-hEBRT averaged 502 kg CO2-eq (95% CI, 484 to 521) and 264 kg CO2-eq (95% CI, 252 to 277), respectively. The largest contributors to total emissions in each group were patient and staff transportation (301.8 vs 196.4 kg CO2-eq, respectively) and LINAC equipment and utilization (175 vs 55.2 kg CO2-eq, respectively). In addition, treatment with mod-hEBRT was found to have, on average, a larger environmental footprint over ultra-hEBRT across all impact categories. The leading contributor to these environmental impacts continued to be patient and staff transportation, which accounted for 91.1% of ozone depletion, 63.2% of smog, 55.3% of acidification, 86.4% of carcinogenics, 53.2% of respiratory effects, 79.7% of ecotoxicity, and 67.9% of fossil fuel depletion in mod-hEBRT. We present the first LCA estimating the environmental footprint of mod versus ultra-hEBRT in ESBC patients. Evaluation of emissions and environmental impacts demonstrate lower carbon and environmental footprints in shorter RT courses that are otherwise clinically equivalent. These data provide the opportunity to consider practice changes in RT delivery that utilize clinically appropriate and ecologically informed regimens in the treatment of ESBC patients.