A comparative study between the gastric mucosa of west Canadians and other dwellers of the Pacific Basin.

The presence of non-neoplastic changes in the gastric mucosa--such as intramucosal glandular cysts, pyloric cells with ciliated metaplasia, with large or small mucus negative vacuoles, and with glassy cytoplasm, as well as extensive intestinal metaplasia (IM)--was investigated in 241 consecutive gastrectomy specimens from the archival files of the Vancouver Hospital situated on the Pacific coast of Canada. A total of 2,938 sections were reviewed (mean number of sections per gastrectomy: 12.24 (range 5-56 sections). Of the specimens with intestinal type carcinoma (known to be promoted by environmental factors), 68.9% contained intramucosal cysts, 35.6% pyloric cells with ciliated metaplasia, 35.6% pyloric cells with large vacuoles, 20.0% pyloric cells with small vacuoles, 4.4% pyloric cells with glassy cytoplasm and 40.0% high IM values. Those percentages were significantly higher than for specimens having diffuse type carcinomas, peptic ulcers, benign gastric tumors or non-neoplastic gastric diseases. The present findings substantiate early results obtained in other populations dwelling along the Pacific Basin. In contrast, dwellers of the Atlantic Basin with gastric carcinoma of intestinal type or other gastric diseases, seldom have similar gastric non-neoplastic changes. It is suggested that the gastric mucosa of Pacific coast Canadians may develop, similarly with inhabitants of other regions of the Pacific Basin, non-neoplastic changes, most notably when harbouring an adenocarcinoma of intestinal type. Environmental factors acting in that basin may account for the results obtained.