Geographic Differences in the Prevalence and Distribution of Large-bowel Polyps - Colonoscopic Findings

Summary

The large-bowel polyp pattern in two widely separated geographic regions of Sweden, Bollnäs in the central part and Trelleborg in the south, was studied prospectively by colonoscopic polypectomy. In Bollnäs 11.8 % of 1,153 patients had neoplastic, and 3.8 % hyperplastic, polyps. In Trelleborg 29 % of 1,040 patients had neoplastic, and 17.3 % hyperplastic, polyps. Furthermore, the Trelleborg patients had, on average, more polyps per patient than their Bollnäs counterparts: 2.0 versus 1.5 neoplastic, and 2.1 versus 1.7 hyperplastic, polyps. There was a marked difference in the anatomic location of the polyps between the two regions: in Trelleborg 55.4 % of the neoplastic, and 40.5 % of the hyperplastic polyps were distributed above the rectosigmoid, compared with 20.9 % and 26.4 %, respectively, in Bollnäs.

The findings offer an explanation of the fact that the incidence of colorectal carcinoma in the Malmö region, close to the Trelleborg area, is the highest in Sweden.

Key words:

Adenomas - differing prevalence of colorectal adenomas - Differing anatomic distribution of colorectal adenomas - Polyps - differing prevalence and distribution of colorectal polyps