Distribution of H.pylori antigens in gastric mucosa and its significance.

OBJECTIVE To investigate the distribution of H.pylori antigens in the gastric mucosa in patients with H.pylori infection, and the relationship between the distribution and gastric cancer. METHODS Of 112 patients confirmed by pathological study to have chronic superficial gastritis, precancerous changes (chronic atrophic gastritis, intestinal metaplasia or atypical hyperplasia) and gastric cancer, 28 were H.pylori negative and 84 were H.pylori positive. H.pylori antigens in the gastric mucosa were detected by immunohistochemistry. RESULTS The H.pylori positive group, comprised 12 of 22 (50.0%) in the chronic superficial gastritis group, 22 of 25 (88.0%) in the precancerous changes group and 13 of 35 (37.1%) in the gastric cancer group. The positive rates of H.pylori antigens in the cytoplasm progressively increased, respectively at 0.0% (0/12), 63.6% (14/22) and 84.6% (11/13) for the same groups (chi(2)=19.76, P=0.000); H.pylori antigens were located in the mucus layer and above the neck of the mucosal gland in 9 of 12 (75.0%) cases with chronic superficial gastritis, at the neck of the mucosal gland and the isthmus in 12 of 22 (54.5%) cases with precancerous changes, below the isthmus in 9 of 13 (69.2%) cases with gastric cancer (chi(2)=25.30, P=0.000). In the H.pylori negative group, no H.pylori antigen was observed. CONCLUSION With the progression of chronic superficial gastritis-->precancerous changes-->gastric cancer, H.pylori antigens progressively migrated from the outer part to the inner part of the cell, and from the superficial to the deep gastric mucosa.