[Detection of early esophageal and gastric cancers by mass screening].

The purpose of mass screening is to decrease the mortality rate of diseases which are fatal if advanced by detecting them at an early and curable stage. From this point of view, we describe here the present state of mass screening, its problems, and the future of mass screening for esophageal and gastric cancer in Japan. The conventional X-ray examination commonly used to detect esophageal cancer does not seem to be effective in detecting the malignancy at an early stage. Therefore, endoscopic examination with Lugol staining for high-risk groups is recommended for the purpose. In contrast, mass screening for gastric cancer by X-ray examination, which has been applied until now, has reduced the mortality rate of gastric cancer. At the same time, however, as various problems are pointed out, some additional investigations have been undertaken to further reduce the mortality rate of gastric cancer. As social circumstances change, and therapy as well as diagnosis for the disease improves, it is necessary to evaluate the accuracy, problems, and limits of the present system to conduct effective and functional mass screening program. The present system must be adapted it to reflect improvements and changes.