Changing how often a popular cancer therapy is delivered would reduce greenhouse gas emissions and improve environmental impact without decreasing cancer survival, according to a study published online May 28 in the journal The Lancet Oncology.

Health care is a major source of greenhouse gas emissions, leading to climate change and public health harms. The study sought to inform environmentally sustainable cancer care by estimating and comparing the environmental and financial effects of alternative, clinically equivalent strategies for the administration of pembrolizumab, an intravenous treatment.

The study focused on the marginal greenhouse gas emissions that are likely to arise when cancer doctors choose to dose the medicine every three weeks instead of every six weeks. The two approaches are clinically equivalent, meaning patients are no worse off if their therapy is given every six weeks. Study authors wanted to estimate the expected societal costs, in environmental and resulting public health terms, that stem from the clinical decision. They estimate that, nationwide, 15,000 fewer tons of CO2 would be emitted annually if cancer doctors adopted the less frequent dosing, largely by reducing demands on patient travel. 

Parth Vaishnav of the University of Michigan School for Environment and Sustainability is one of the co-authors. 

Read more on the Michigan Medicine website.

Study: Projected environmental and public health benefits of extended-interval dosing: an analysis of pembrolizumab use in a US national health system