Intestinal metaplasia of the stomach. I: Quantitative analysis in gastric peptic ulcer and in incipient adenocarcinoma in Japanese subjects.
A novel method of quantitation of the extent of intestinal metaplasia (IM) was applied to 50 resected stomachs from Japanese subjects; 25 with peptic gastric ulcer, 25 with incipient adenocarcinoma. The total length of the IM was significantly larger (p less than 0.05) in incipient adenocarcinomas than in peptic ulcers; the total length of the gastric mucosa analyzed being similar in the two groups. The intestinal metaplasia index (IMI; i.e. the ratio between IM and the length of the gastric mucosa analyzed) in incipient adenocarcinomas was significantly higher (p less than 0.05) than in gastric ulcers. In incipient adenocarcinomas, the IMI decreased significantly (p. less than 0.001) from lesser towards greater curvature. In peptic ulcers, the decrease was less abrupt. In 12 of the 25 specimens, the incipient adenocarcinoma was classified as intestinal type, and in the remaining 13 specimens as diffuse type. The total length of the IM was significantly larger (p less than 0.01) in specimens with intestinal type adenocarcinoma than in specimens with diffuse type; the total length of the gastric mucosa investigated being similar in the two groups. The IMI was significantly higher (p less than 0.01) in specimens containing intestinal type adenocarcinoma as compared to those with diffuse type adenocarcinoma. This was valid for the lesser curvature, for the mucosa adjacent to the lesser curvature, and for the mucosa by the greater curvature. From the results, it is apparent that intestinal metaplasia is a widely occurring phenomenon not only in specimens with intestinal type incipient adenocarcinoma or with diffuse type incipient adenocarcinoma, but also with benign peptic ulcer. The difference resides in that the metaplastic mucosa is more universally distributed in specimens with incipient intestinal adenocarcinomas (provided that longitudinal mucosal areas are considered in the comparison). The quantitative method herein reported will be applied in the future to compare the extent and distribution of intestinal metaplasia in gastric specimens from various geographical regions having disparate incidences of gastric ulcers and carcinomas.