Current status of endoscopic gastric cancer screening in South Korea

Abstract

Cancer screening in the stomach, breast, cervix, colon, liver, and lung is offered by the Ministry of Health and Welfare in South Korea. The National Health Screening Program aims to decrease cancer-related mortality by detecting early-stage cancers. In addition to cancer screening provided by the government, opportunistic cancer screening is provided to all Korean employees by their employers. The Korea Central Cancer Registry collects data from mass screening and opportunistic screening, so the exact participation rate is calculated. Guidelines recommend endoscopy for Koreans aged between 40 and 74 years because gastric cancer-related mortality significantly decreases. However, the mortality did not decrease in older subjects nor in the subjects who were screened with UGIS. In 2020, 90.2% of gastric cancer screening was performed with endoscopy in South Korea. An internet reservation system for cancer screening prevents endoscopists from overwork. The gastric cancer screening rate was 44.7% in 2010, increased to 62.9% in 2019, and then decreased in 55.7% in 2020 due to the pandemic of severe acute respiratory syndrome coronavirus 2. The rate of gastric cancer or adenoma in endoscopic screening was 0.48%. The age-standardized incidence of gastric cancer per 100,000 persons decreased by 0.2% per year until 2011, and then decreased by 4.6% per year thereafter. The age-standardized mortality rate of gastric cancer per 100,000 persons decreased from 57.6 in 1985 to 7.1 in 2019, passing Japan’s rate in 2012. The five-year survival rate increased from 43.9% in 1993-1995 to 77.5% in 2015-2019. These changes are reflected by the increase in the rate of early-stage gastric cancer from 28.6% in 2009 to 63.6% in 2019. The prevalence of Helicobacter pylori (H. pylori) infection has been decreasing and the eradication rate has been increasing in Korea, suggesting that the gastric cancer screening program needs adjustment according to the status of H. pylori infection. Therefore, biannual endoscopic screening should not be required for all Koreans in the future. Gastric cancer screening should be initiated after discriminating between H. pylori-naïve, -infected, and -eradicated subjects by trained endoscopists in diagnosing H. pylori infection status using endoscopy and serum assay findings. H. pylori should be eradicated properly in infected patients as the primary prevention of gastric cancer, before starting secondary prevention by biannual endoscopic screening.