BLADDER SUBSTITUTES, BILE-ACIDS AND THE RISK OF COLORECTAL-CANCER - AN EXPERIMENTAL-STUDY

There is a large body of evidence relating the causation of colon canc er to bile acids. Using an animal model, we attempted to adress the qu estion, i.e., the incidences of carcinogenesis in the colon as consequ ences of resection of different bowel segments, predominantly employed in the construction of various forms of intestinal bladder substitute s. 60 male Wistar rats were operated. Group 1 served as control, in gr oup 2, 20 cm of terminal ileum was resected, and rats in group 3 under went resection of the distal 10 cm of the ileum and 7 cm of the proxim al colon. All rats were killed 6 months after surgery and the colon wa s removed. After examination under 40-fold magnification, in the absen ce of tumors, 3 biopsies were performed at predetermined positions and underwent histological processing. Even if no tumor was found it woul d be incorrect to conclude that these results would have an appeasing relevance. The complex and highly different fecal bile acid profiles o f the rat compared to man makes it impossible in this context to draw analogies between the rat model and human colonic carcinogenesis. Furt hermore, 6 months of observation in the rat might be too short for 'sp ontaneous' colonic carcinogenesis. Nevertheless, there exists evidence from epidemiological studies to implicate bile acids as an etiologica l factor in the development and growth of colorectal cancer. Therefore , the importance of colorectal cancer in urologic surgery patients mus t be kept in perspective. In this direction, further studies are requi red besides the application of known appropriate preventive measures.