Impact of the COVID-19 Pandemic on Gastric Cancer Screening in South Korea: Results From the Korean National Cancer Screening Survey (2017-2021).

Purpose: The coronavirus disease 2019 (COVID-19) pandemic has significantly disrupted cancer screening services worldwide. We aimed to measure the impact of COVID-19 on gastric cancer screening rates based on age, sex, household income, and residential area.

Materials and methods: We analyzed data from the Korean National Cancer Screening Survey from 2017 to 2021 for adults aged 40-74 years. We evaluated the gastric cancer screening rate within two years in accordance with the National Cancer Screening Program protocol recommendations and that within the previous year. We compared the trends in the pre- and post-COVID-19 outbreak periods.

Results: Before the COVID-19 outbreak, there was little change in the gastric cancer screening rates until 2019. After the COVID-19 outbreak, the screening rate as per recommendation decreased from 70.8% in 2019 to 68.9% in 2020 and that for one year decreased from 32.7% in 2019 to 27.2% in 2020. However, as the COVID-19 pandemic continued after 2020, both gastric cancer screening rates as per recommendations and for one year rebounded. Although a similar trend was observed for the upper endoscopy screening rate, the upper gastrointestinal series screening rate decreased from 7.8% in 2020 to 3.1% in 2021. During the pandemic, the screening rate decreased among younger adults (40-49), those residing in metropolitan regions, and those with high incomes.

Conclusions: Despite a decline in gastric cancer screening rate during the COVID-19 pandemic, the rate surged in 2021. Further studies are needed to estimate the impact of cancer screening delays on future cancer-related mortalities.