Evaluating the Short- Term Environmental and Clinical Effects of a Radiation Oncology Department's Response to the COVID-19 Pandemic (STEER COVID-19)

Background: During the COVID-19 pandemic, many radiation oncology departments worldwide adopted the use of shorter and more intense hypofractionated regimens. Hospital foot traffic was reduced through virtual care and work. This study’s primary objective was to assess the environmental impact of these strategic changes by identifying sources of carbon dioxide equivalents (CO2e). The rate of radiation-related adverse event from the increased use of hypofractionated treatments was assessed. Methods: All patients treated with external beam radiation therapy from April 1, 2019, to March 31, 2021 at our single institution were identified (n=10,175) along with their radiotherapy visits (176,423 fractions), and unplanned visits to the radiation nursing clinic (RNC) or emergency (ER) department. Out-patient hospital and virtual visits (n=75,853) during this same period were also analyzed. Environmental impact measures, including linear accelerator power usage, patient travel distances, personal protection equipment (PPE) consumption, and the use of information technologies were all converted into CO2e. Results: The use of curative hypofractionated regimens increased from 17% to 27% during the pandemic year. Reduction in patient travel reduced 510,711 – 685,552 kg CO2e. Conversely, virtual care and work, and increased PPE use augmented CO2e generation by 57,717 kg. The net change in carbon footprint was -573,138 kg CO2e during the pandemic year. Comparing patients in the pre-pandemic vs . pandemic year, there was a significant reduction in the proportion of hypofractionated patients who needed a visit to either the RNC (39% vs. 25%; p<0·001) or ER (6% vs. 2%; p<0·001) during and within 90 days of radiotherapy. Discussion: This is the first study to demonstrate the environmental benefits of increased use of hypofractionated regimens and virtual care, while assuring that there were no added acute radiation-related adverse events. Our findings support their continued use as one of many long-term strategies to reduce the environmental footprint of healthcare delivery.Funding Information: The authors have no external funding source to declare.Declaration of Interests: The authors have no conflicts of interests to declare that may be affected by the publication of the paperEthics Approval Statement: A waiver of individual patient consent was granted for this study by our institution’s Research Ethics Board.