Masaru Matsumoto

Ratio of primary and secondary bile acids in feces

PURPOSE: Increases in fecal bile acids may play a role in colorectal carcinogenesis. The authors tested the hypothesis that high concentrations of primary and secondary bile acids are more common in patients with colon cancer than in patients with other gastrointestinal diseases. METHODS: In this retrospective study the secondary bile acid deoxycholic acid and the primary bile acid cholic acid were measured in the feces by enzyme-linked immunoabsorbent assay in 63 patients with colorectal cancer, 24 patients with gastric cancer, 11 patients with biliary disorders, and 47 healthy volunteers. RESULTS: Preoperatively, the mean deoxycholic acid values tended to be higher and the cholic acid values were significantly lower in patients with colorectal cancer than in healthy subjects. Patients with other gastrointestinal diseases had lower deoxycholic acid and cholic acid values than healthy subjects. In healthy subjects the deoxycholic acid to cholic acid ratio ranged from 0.10 to 2.86 (mean, 0.88), but in almost two-thirds, the ratio did not exceed 1. In contrast, the mean preoperative ratio in patients with colorectal cancer was 2.26 (range, 0.06–7.17;P<0.0001) and tended to be higher in patients with advanced cancer and in those with sigmoid and rectal tumors. If 1.1 is taken as the upper limit of normal for deoxycholic acid to cholic acid ratio, 67 percent of patients with colorectal cancer had an abnormal value preoperatively. CONCLUSION: A high deoxycholic acid concentration and deoxycholic acid to cholic acid ratio may be indicators of colorectal cancer. Further study is needed to improve sensitivity and specificity, perhaps by combining fecal bile acid measurements with other tests, and a large prospective trial may be warranted to determine whether these measurements have value in screening for this common cancer.

DIAGNOSTIC SIGNIFICANCE OF MEASUREMENT OF FECAL BILE ACIDS IN COLORECTAL CANCER PATIENTS

Fecal bile acid values in 23 patients with colorectal cancer were shown to have diagnostic significance. Deoxycholic acid (DCA) and cholic acid (CA) were measured using the enzyme-linked immunosorbent assay method and the DCA:CA ratio was used for the pre- and postoperative comparison. The postoperative ratio was found to be lower than the preoperative ratio in every patient. This finding indicates the clinical usefulness of the DCA:CA ratio in monitoring the progress of colorectal cancer. This type of monitoring may be useful for screening patients for colorectal cancer in high-risk populations.

Significance of Fecal Bile Acid Ratio in Colorectal Cancer Patients

Fecal bile acid values in 10 colorectal cancer patients have been demonstrated to have diagnostic significance. Deoxycholic acid (DCA) and cholic acid (CA) were measured by Emzyme Linked Immunosorbent Assay (ELISA) method and their composition ratio (DCA/CA) was used for the pre and post operative comparison. The post operative ratio was found to be lower than the pre operative ratio in every patient. The result can be anticipated the clinical utility in the diagnosis of colorectal cancer patients.