Response letter: Handling of COVID-19 positive lung cancer patients during the pandemic.

To the Editor,

We would like to thank Troost et al. [1] and Magrini et al. [2] for opening a broader discussion about radiotherapy treatment of COVID-19 positive lung cancer patients during the time of the pandemic [3]. We propose differentiating two separate aspects and risk categories which need to be considered in this situation.

First, there are risks to the lung cancer patient him- or herself from the COVID-19 infection, the thoracic radiotherapy, and the combination of the two. Only very limited (or even no) safety data are available about a potential interaction and added risk for more frequent or severe pulmonary toxicity, in both symptomatic and asymptomatic COVID-19 positive patients. We could extrapolate from experiences with other viral or bacterial pulmonary infections, where we have learned when to postpone or interrupt radiotherapy vs. when it is sufficiently safe to treat. We could also extrapolate the potential harm to lung cancer patients in delaying or interrupting radiotherapy for a short period of time until the patient is recovered and not infectious anymore. Additionally, we proposed factors to be considered in the decision-making process whether to interrupt radiotherapy in patients treated with radical radiotherapy and diagnosed as COVID-19 positive: COVID-19-related symptoms, symptoms of lung cancer, and infection with COVID-19 near the end of treatment. These factors do allow balancing the patient-individual risks of the COVID-19 infection and lung cancer, especially in case of longer delays or interruptions. Ultimately, however, there is very limited evidence to guide the trade-offs between the risk of reduced oncologic control from delays (or interruptions) in treatment vs. the potential harms from radiating a patient with an active COVID-19 infection.

We wish to clarify that our practice recommendation does not advise “to restrict curative cancer treatment to COVID-19 negative cohorts” as mentioned by Troost et al. – this would be indeed unethical. We addressed the questions of postponing or interruption of radiotherapy, not restricting treatment.

Secondly, our ESTRO & ASTRO practice recommendation specifically addresses the issue of COVID-19 infections in situations of the pandemic as declared by the WHO, and clearly distinguishes between medical practices during two pandemic states, also referred to as “contingency standard of care” and “crisis standard of care.” Our practice recommendations are valid only in the context of these pandemic scenarios, where postponing or interrupting the radiotherapy treatment of COVID-19 positive patients may also contribute to contain the pandemic by protecting health care workers, other patients and fellow citizens. We are hopeful that eventually there will be broad immunity to SARS-Cov-2 (preferably through vaccination), which will make modifications of radiotherapy practice in patients with and without COVID-19 infection redundant, at least from a public health perspective.

We hope that these clarifications further contribute to balance the competing risks associated with the COVID-19 pandemic and the lung cancer diagnosis and radiotherapy, and we again conclude that treatment decisions should be individualized and that practitioners should use their clinical judgement, including when to treat a COVID-19 positive patient.