The Impact of the COVID-19 Pandemic on the Radiation-Induced Cancer Risk in Zanjan, Iran

The coronavirus resulted in a global pandemic and infected millions of people worldwide in 2019. The number of chest CT scans significantly increased due to the virus's effect on the upper respiratory tract. This retrospective cross-sectional analytic study aimed to investigate the COVID-19 effect on the number of chest CT scans and to estimate the probability of radiation-induced cancers as a result of the incremental number of scans in hospitals in Zanjan, Iran.

This study included all chest CT scans performed during a three-month period before the pandemic (2019) and the pandemic (2020). In 2020, the scans were meticulously examined for COVID-19 signs, and relevant epidemiological and dosimetric factors were recorded to calculate the risk of radiation-induced cancer using the IRCP103.

The results reveal a four-fold increase in the number of scans in 2020, with 9095 scans compared to 2235 in 2019. Patients referred for a chest CT scan during the COVID-19 outbreak were significantly younger. Although the Dose-length Product (DLP) decreased in 2020, the anticipated number of new cases of radiation-induced cancers exhibited an approximately four-fold increase for different organs in the thorax region. Also, 55.6% of CT scans were considered normal in 2020.

The current study shows that the high probability of radiation-induced cancers should be considered the long-term effects of the COVID-19 pandemic.