[Current issues and future prospects of gastric mass survey].

In general, it is necessary to consider morbidity rate and mortality in the population at risk when mass survey for cancer is performed. From our long-term follow-up study, it is clearly suggested that gastric mass survey contributed toward reducing the mortality from stomach cancer. However, the effectiveness of gastric mass survey depends on the screening system. The screening system with a low grade in its accuracy and reliability may also cause spoil the effectiveness of mass survey.