“Green” prescribing may limit the environmental impact of oncology

Side-effects of cancer treatment affect not only patients, but also the health of our planet which, in turn, influences cancer risk and the way cancer care services are delivered. If human health and the future health of the planet are strictly interrelated, how can medical professionals contribute toward stopping this vicious cycle? “Although there is a growing awareness that our professional choices have an impact on the environment, guidelines which may advise our practice towards sustainability have not been developed so far,” says Dr Mathilde Jalving, from the University Medical Centre Groningen, Groningen, the Netherlands, Chair of the ESMO Climate Change Task Force.

So-called “green” prescribing is gaining increasing attention as one of the potential solutions to reduce the environmental impact of oncology. What does it consist of?

When prescribing medication, both in oncology as well as in other medical areas, we need to start taking the environment into account. It is clear that drugs harm the environment. For example, small amounts of hormonal drugs which are taken by patients accumulate in sewage systems and act as endocrine disruptors in fish affecting their development. Also, intravenous administration of therapies produces more plastic waste than giving the same drugs orally, due to the use of infusion materials. Green prescribing firstly means not prescribing drugs unless there is a clear, evidence-based benefit, stimulating de-escalation studies and studies into earlier stopping of, ie adjuvant therapies or therapies resulting in durable responses. Knowledge on the environmental impact of drugs is especially relevant when there is a choice between treatments that are comparable in terms of benefit/harm ratio. There is a clear need for “green” prescribing guidelines to address our daily choices. However, tools to assess the climate impact of a medicine based on its manufacturing process, the way of administration and the related waste products have not been developed yet. There is a lot of interest in this topic, and as oncologists we should look at how to translate the general principles of “green” prescribing into cancer care and eventually integrate them into the global curriculum for medical oncologists. As the climate crisis progresses, and the goals to cut greenhouse emissions by 2030 will probably not be met, we need to teach our students how to look at sustainability as a driver of their profession.

Sustainability is a hot topic today. What does it mean in the oncology landscape?

In general, sustainability means that our current human activities should not negatively affect future generations. In oncology, this term implies that professionals should be aware not only of the potential effects their choices in daily practice may have on the environment, but also of the direct impact the climate crisis has on how cancer develops and is treated. Firstly, pollution – which goes hand in hand with the climate footprint and CO2 output – is a modifiable risk factor for cancer, so the incidence of some malignancies is higher in geographical areas where exposure to pollutants is greater. Another aspect is a rising incidence of extreme weather conditions which disrupt the access of patients to cancer care, as some recent data clearly show (Lancet Oncol. 2018 Sep;19(9):e482-e499). As was observed during the lockdowns due to the COVID-19 pandemic when access to cancer care was reduced, natural disasters like the floods which have recently hit Italy, may negatively impact early diagnosis, optimal treatment and ultimately on survival rates.

Do you think that the oncology community is aware of the direct impact that their everyday clinical activities have on the environment?

Some oncologists are very engaged and enthusiastic about trying to take steps toward sustainability, but they often report that they struggle to convince their own colleagues that this is a key issue. There is still a gap in education, and one of the aims of the ESMO Climate Change Task Force is to provide educational materials which support professionals to increase awareness in their own communities. We are increasingly realising that communication around health and climate issues needs to be tailored to different countries where the political agenda gives variable priorities.

ESMO is pioneering in the field. The first activity of the Task Force was to estimate the greenhouse gas emissions associated with attendance at the ESMO Congress, and found that on average each attendee generated about 1,500 kg of carbon. This kicked off a series of actions toward making the Society and its events more sustainable, including stimulating train travel, the digitalisation of ESMO scientific journals, waste reduction at events, attention to reducing air conditioning and gadgets and providing more sustainable food choices.

What can healthcare professionals do in their daily clinical activity to be more sustainable and respect the environment?

Obviously, our primary focus is to take care of our patients and deliver high quality care. However, within these boundaries, we can take simple individual actions to give a good example: as simple as limiting travelling to lessen the CO2 emissions globally. Nobody is perfect, so I do not think the message should be that you can never take a plane to attend a congress, but whenever there is an environmentally friendly alternative, it should be pursued.

There are also some initiatives at a hospital level that may reduce the impact that oncology-related human activities have on climate change. For instance, unnecessary patients’ travel to our facilities during their care path can be reduced by replacing some appointments with phone calls. Also, treatment de-escalation, when possible, results in a wiser administration of medication and reducing potential waste. More in general, a re-organisation of services that aims to avoid all unneeded tests may translate into a more sustainable allocation of resources – which is a win-win strategy not only for the planet, but also for our healthcare systems which are being pressured by an increasing incidence of cancer.

I believe that first focusing on the immediate return of “green” practices as such could be a key driver to help the oncology community implement the first changes. Reducing our environmental footprint is a huge challenge, but this should not prevent us committing to reducing our impact on climate change and taking the first steps.