The limitation of detectability and curability in terms of current techniques (screening and details) were sought in otherwise healthy examinees. Not a few cancers were present in the alimentary tract, except for the stomach, in these otherwise healthy examinees who voluntarily underwent gastric cancer mass screening. The prognosis of alimentary tract cancers deteriorates in the descending, following order: colon cancer, stomach cancer, and esophageal cancer. The survival rate of primary liver cancer, cholecyst cancer, and pancreas cancer is extremely low. Unless new techniques are developed in these diagnoses, no improvement in the survival rate can be anticipated.