Advancing Gastric Cancer Prevention in Korea: Current Strategies and Future Directions.

[BACKGROUND] Korea has historically borne a high burden of gastric cancer, although substantial epidemiological transitions have occurred over recent decades. Gastric cancer was the most common cancer until 2018, but declined to fifth by 2022. Gastric cancer incidence has decreased steadily, accompanied by marked reductions in mortality and substantial improvements in survival, with 5 year overall survival rate now exceeding 75%. During this period, Helicobacter pylori (H. pylori) seroprevalence has shown a decreasing trend, especially in younger generations.

[METHODS] Randomized controlled trials conducted in high-risk groups have demonstrated that H. pylori eradication significantly reduces gastric cancer risk. To further evaluate the role of H. pylori eradication as a primary prevention strategy in the general population, HELPER is currently ongoing in Korea in collaboration with the International Agency for Research on Cancer. For secondary prevention of gastric cancer, the Korean National Cancer Screening Program (KNCSP) was launched in 1999 and provides biennial endoscopic screening for adults aged 40 years or older.

[RESULTS] The HELPER study had screened H. pylori status in > 12,000 average-risk Korean participants who had participated in KNCSP up to 2019. Individuals with H. pylori infection were randomized to receive either bismuth quadruple therapy or placebo. The participants have been followed up through the KNCSP, and an interim analysis is planned after a 6 year follow-up period. Secondary prevention through the KNCSP has achieved high participation rates and is strongly associated with reduced gastric cancer mortality, stage migration to early disease, and increased use of endoscopic treatment.

[CONCLUSIONS] The current uniform screening strategy does not incorporate individual risk stratification and is costly. Future integration of H. pylori eradication and objective assessment of gastric atrophy into risk-adapted screening and surveillance strategies may optimize effectiveness, reduce healthcare costs, and further decrease the burden of gastric cancer in Korea.