Variation of serum bile acids in patients with colorectal adenomas during a one-year follow-up

We were recently able to show that patients with colorectal adenomas have an increased serum level of the secondary bile acid deoxycholic acid [Bayerdörffer et al.: Gastroenterology 1993; 104:145-151]. The course of individual serum bile acids was followed for 1 year in a random subgroup of these patients. The individual serum bile acids of 39 patients, 10 men with adenoma, 12 men without adenoma, 8 women with adenoma, and 9 women without adenoma, were determined at 6-month intervals by gas liquid chromatography (GC). The mean individual differences in serum bile acids between baseline and 6-month follow-up and baseline and 12-month follow-up ranged from +19 to -15 nmol/l in men with adenoma, and from +66 to -64 nmol/l in men without adenoma. In women, the ranges were +73 to -74 nmol/l in those with adenoma and +33 to -81 nmol/l in those without adenoma. The variations of the relative percentages of the individual bile acids in the three investigations were lower than those of the absolute values. The differences between the baseline, the 6-month, and the 12-month follow-up were not significant for the major bile acids deoxycholic acid, chenodeoxycholic acid and cholic acid. The main finding, namely an increase in the serum levels and the relative proportion of deoxycholic acid in men with colorectal adenomas remained unchanged throughout the follow-up. The data indicate that measurement of the bile acid pattern by GC is a useful and reproducible parameter in investigating the role of secondary bile acids in the pathogenesis of colorectal cancer.