ESTRO 2024 - Abstract Book

S2741

Interdisciplinary - Global health

ESTRO 2024

1988

Digital Poster

Modeling the carbon footprint of external beam radiotherapy and the impact of hypofractionation

Dimitri Vanmarcke 1 , Olena Holubowska 2 , Ate Poorthuis 2 , Bram Mangelschots 1 , Jean-François Daisne 1

1 University Hospitals Leuven, Department of Radiation Oncology, Leuven, Belgium. 2 KU Leuven, Department of Geography and Tourism, Leuven, Belgium

Purpose/Objective:

Climate change is one of the biggest threats to public health. Paradoxically, the health care sector is an important emitter of greenhouse gases so every effort should be made towards sector decarbonization. In an analysis performed by Chuter et al. (Phys Medica 2023), patient transport was estimated to be up to 80% of the carbon footprint of external beam radiotherapy (EBRT). The evolution towards hypofractionation can reduce patient transport and usage of the linear accelerator (LINAC). We modelled the carbon footprint of patient transport for an entire Belgian academic radiotherapy department for one year. We then evaluated the impact of best evidence hypofractionation on the CO 2 equivalent (CO 2 e) emissions of transport and, for prostate cancer, on energy consumption against this baseline.

Material/Methods:

We performed a retrospective study of all patients treated with EBRT in 2019 in the radiation oncology department of the University Hospital Leuven (Belgium). The greenhouse gas emissions of transport, reported as CO 2 e emissions, were modelled by considering the kilometres between the home of the patient and hospital as well as the number of visits necessary for the treatment (comprising simulation appointment(s) and acute follow-up). Since there was no registration of the mode of transport or exact car type, we based ourselves on the reported average CO 2 emissions for newly registered passenger cars in Belgium in 2018, which is 147.5 g CO 2 /km (European Environment Agency, 2023). Secondly, the impact of the most hypofractionated schedules according to the current (July 2023) best scientific evidence was implemented in the model (see table below). The changes in fractionation schedules are mentioned in the data table. Lastly, the energy consumption of a Varian TrueBeam® LINAC was measured with a power logger for one day to calculate CO 2 emissions based on the Belgian energy mix.