Relationship between cholecystectomy and ascending colon cancer.

A retrospective study involving 706 sample cases of large bowel cancer grouped by subsite (ascending colon, transverse colon, descending colon, sigmoid colon, ana rectum), sex, and age identified during the Third National Cancer Survey (Pittsburgh SMSA, 1969--1971) was recently completed. The basic strategy of this comparative study was to determine whether the frequency distribution patterns of both demorgraphic characteristics and environmental factors differed among persons with subsite-specific cancer of the large bowel. Based on the information provided in the hospital records there was a gradient of previous cholecystectomy history from ascending colon cancer (10.5%) to rectal cancer (2.1%) in those patient records whose only gastrointestinal surgery indicated was cholecystectomy. For patient records in which the only surgical operation was cholecystectomy, or cholecystectomy plus other gastrointestinal surgery, the gradient persisted as one moved from the right to the left subsites of the large bowel. No relationship with respect to other types of gastrointestinal surgery was observed. It is clear, however, that a bias associated with the review of hospital records can account for this relationship and, therefore, the finding may be spurious. On the other hand, there is increasing evidence of a relationship between bile acid metabolism and carcinoma of the colon. It might be considered that the right side of the colon would be most likely affected by the potential carcinogenic effect of certain bile acid metabolites.