Is previous radiation to the lungs a risk factor for death due to COVID-19?

Bottom Line

This study found that a history of lung irradiation increases mortality risk in COVID-19 patients.


Kabarriti, R. et al. Extent of prior lung irradiation and mortality in COVID-19 patients with a cancer history. Advances in Radiation Oncology (2020).

Date Published:

20 May 2020


The study gathered 107 patients who tested positive for COVID-19 and had previously received radiotherapy for cancer. The outcome of interest was overall survival duration, or the time between the diagnosis of COVID-19 and death. Researchers found that having had radiotherapy for cancer was associated with a mortality risk of approximately 35%. Further, patients that received radiotherapy within one month to one year before testing positive for COVID-19 had a higher mortality risk. This timeframe overlaps with the typical presentation of a complication called radiation pneumonitis, in which radiation therapy causes the release of inflammatory molecules resulting in damage to the lung tissue. Given the small sample size and short follow up, further investigations are needed to fully understand the effects of lung irradiation. Implications may involve decreasing the threshold for hospitalization in those with prior lung irradiation as well as educating these patients to be more attentive in their exposure risk.

Summary by: Eugenia Yeung