[Clinico-morphological characteristics of background diseases in stage I stomach cancer].

A study on alterations occurring in gastric mucosa in cases of stage I stomach cancer identified chronic gastritis involving gland atrophy of varying degree as the basic background feature, with intestinal metaplasia and dysplasia being common manifestations of precancerous lesion development. Malignant transformation of hyperplastic polyps and adenomas occurs in areas in which dysplasia of metaplastic epithelium tends to spread. Stomach cancer development from gastric ulcer seems unlikely. Morphological factors should be considered, when groups of high risk for stomach cancer development are identified among cases of chronic gastric diseases.