I have been in trouble because TDDW gave me a lecture title with no correct answer. In my personal opinion, I don't think there is a need for surveillance endoscopy for patients with low-risk precancerous conditions after H. pylori eradication. However, this policy should be decided based on the understanding of the government financial situation and the citizen of each country.

Helicobacter pylori (H. pylori) was declared a human carcinogen in 1994. It is well known that the evidence has now accumulated to show that at least 95% of gastric cancers are etiologically related to H. pylori. A meta-analysis published in 1999 reported that the risk of gastric cancer with H. pylori infection had an odds ratio of 2.04 (95% confidence interval [CI], 1.65–2.45). Similarly, a 2007 study in nine European countries reported that the risk of gastric cancer with H. pylori infection had an odds ratio of 2.6 (95% CI, 1.7–3.9).

Gastric cancer is the second most common cause of death from cancer worldwide, and especially in Eastern Asia countries such as China, Japan and Korea. Thus, the need for efficient, cost-effective and practical nationwide mass screening systems for gastric cancer in Eastern Asia remains controversial. In Japan, however, there has been a progressive increase H. pylori naïve and H. pylori eradicated subjects, consequently, the number of gastric cancer deaths has begun to decline in recent years. In near future, selective screening or target screening should be considered even in countries with frequent gastric cancer.

H. pylori is a common chronic infection that has been confirmed to be significantly associated with gastric cancer. In other words, the gastric mucosa with severe atrophy and/or intestinal metaplasia is at high risk for gastric cancer. Therefore, the high-risk population is basically an elderly person, in addition, male, smoking, high-salt diet and family history have been reported as risk factors. Conversely, even those infected with H. pylori are at low risk for those who received H. pylori eradication therapy at a young age. When it comes to the need for surveillance endoscopy for such subjects, the answer is “no”. However, unfortunately, it is not clear what time the “point of no-return” is. Therefore, once again, each country must consider when and not a surveillance endoscope for the low-risk group is necessary for their respective circumstances.

Finally, the definitions of surveillance and screening are given. I hope it will be helpful to everyone. “Surveillance” systematically collects, analyzes, and interprets the data necessary for planning, implementing, and evaluating disease control by continuously monitoring the outbreak status and transition of diseases, and promptly obtains the results. Moreover, it is regularly returned and is used for the purpose of disease prevention and management. “Screening” is conducted as a public health activity for the population. The benefit is defined as the mortality reduction effect. Screening by risk stratification may be cost-effective. However, it is difficult to control the examinee, and it is uncertain whether an appropriate intervention will be made. For example, the HPV test, which is a carcinogenic risk of cervical cancer, is being introduced, but it has been reported that the accuracy control is difficult and the consultation rate is low. Verification of whether or not it will proceed as planned (surveillance) and appropriate measures to proceed is required.