[Problems associated with mass-screening system for gastric cancer in Japan].

In the mass-screening system for gastric cancer, subjects are primarily examined by contrasted indirect roentgenography and if secondary examination is diagnosed to be necessary, they are examined by contrasted direct roentgenography or gastric fiberscopy. Methods for increasing the efficiency of this system from the standpoint of cost-effectiveness were studied, and the basis for decision of whether or not serological examinations such as of serum pepsinogens and serum anti-Helicobacter-antibodies should be brought in to the system, and in what manner serological examinations should be brought in to the system if proven to be effective were examined. Problems found in the present practiced system and the proposed new system with serological examinations were repetition interval for examinations, selection of high-risk subjects and communication between subjects and the medical staff or among the members of the medical staff. Analysis by receiver operating characteristics curve should be included when serological examinations are indicated. In addition whether the mass-screening system for gastric cancer produces an actual reduction in death by gastric cancer should be confirmed after the system is made more efficient.