Endoscopic Characteristics of Gastric Polyps and Their Background Mucosa on the Gastric Body

We investigated the endoscopic and histopathological characteristics of 112 gastric polyps on the gastric body. According to the histopathological findings of the glands in the biopsy specimens, we classified the polyps into 6 categories; dense fundic gland type (group A), sparse fundic gland type (B), mixed fundic and pyloric gland type (C), pyloric gland type (D), complete atrophic gland type (E) and others (F). The grade of atrophic gastritis was defined by the fundic-pyloric border type of the stomach, and was found to change from mild to severe respectively in groups A to E. The gastric area type of background fundic gland mucosa also changed from F0 to F3 in parallel with the order of the groups A to E. Thirty-five of the 36 polyps in group A, all 19 in group B, 2 out of 3 in group C, 1 of 4 in group D, and the 1 in group E were located on the dye-endoscopically defined fundic gland mucosal area. The gland type of biopsy specimens which were obtained from the mucosa adjacent to the polyps changed from fundic to fundic-pyloric and to pyloric type in groups A to E respectively. In conclusion, the histopathological findings of polyps on the gastric body reflect the background mucosa, and in particular the extent of the atrophic change of the stomach. The majority of polyps, either fundic gland polyps (groups A and B) or hyperplastic polyps (groups C, D and E), on the gastric body were found to be the same gland type as their respective background mucosa. They thus seem to fall into the same category as hyperplastic polyps of background mucosal origin but are not the same as a hamartomatous polyp.