Quantitative changes of gastric mucosa during carcinogenesis using stereological methods.

PURPOSE: To investigate the effects of helicobacter pylori (H. pylori) infection on the quantitative changes of gastric mucosa in cancerous and precancerous lesions using stereological methods.

METHODS: One hundred and twenty-two gastric samples were studied. After determination of H. pylori infection, 42 gastric tissues of intestinal metaplasia (IM) patients, 38 specimens from dysplasia (DYS), and 42 specimens from gastric cancer (GC) types were selected from the pathology archive of Imam Ali Hospital, Zahedan, Iran. Gastric tissues were sectioned and stained with p53 and Ki-67 immunohistochemical (IHC) method and haematoxylin/eosin (H&E). Then, the numerical density (NV) of p53-positive, Ki-67-positive cells, eosinophil and polymorphonuclear (PMN) cells were estimated using dissector counting technique in IM, DYS and GC lesions.

RESULTS: In IM, DYS and GC specimens, the NV of p53-positive cells in the presence of H. pylori infection (H. pylori+) was significantly higher than in H. pylori absence (H. pylori-). The NV of Ki-67- positive cells only in DYS specimens, showed significant difference between H. pylori+ and H. pylori- groups. The NV of eosinophil cells in DYS and GC specimens in H. pylori+ groups were significantly higher than in H. pylori- groups and the NV of polymorphonuclear cells in IM specimens showed significant difference between H. pylori+ and H. pylori- groups.

CONCLUSION: The results showed that H. pylori infection could cause significant quantitative changes in the cellular structure of gastric mucosa that might be influential on gastric carcinogenesis.