Faecal bile acids, dysplasia, and carcinoma in ulcerative colitis.

A prospective study was undertaken between 1974 and 1985 of 102 patients with extensive ulcerative colitis (UC) of more than 10 years' duration. Faeces were collected for measurement of faecal bile acid concentrations (FBA), and the clinical outcome was recorded. The average faecal bile acid value among the 14 patients who showed carcinoma or definite dysplasia in the excised large bowel (9.86 [SE 0.81] mg/g FBA) was higher than in the 88 patients without dysplasia or carcinoma (7.51 [0.24] mg/g). These results lend support to the theory that bile acids are causally related to colorectal cancer.