DUODENAL BILE-ACID PROFILES IN PATIENTS WITH COLORECTAL-CANCER OR POLYPS

Objective: To assess the detailed duodenal bile acid profile in patien ts with colorectal cancer or polyps compared with controls. Design: Pa tients were matched where possible with controls excluding most factor s known to affect the bile acid profile. Methods: Thirty-three patient s (11 in each group) had duodenal bile collected endoscopically and bi le acids were measured by gas liquid chromatography. Results: Patients with colorectal cancer had a higher proportion (median, range) of sec ondary bile acids (37.3, 24.1-50%) in their biliary bile compared with controls (25.2, 15.4-56.9%; P = 0.02; Mann-Whitney U-test) and also w hen compared with patients with polyps (28.2, 10.1-41.7%; P = 0.057). These differences were not significantly correlated to bowel transit t ime or daily stool weight. Patients with cancer had a lower proportion of cholic acid (28.7, 23-34.6%) than controls (34.3, 21.1-67.3%; P = 0.026) and patient with polyps (35.9, 28.3-51.8%; P = 0.007). The rati o of cholic acid to its metabolites was also found to be lower in the cancer group (0.54, 0.39-0.64) compared with both controls (0.61, 0.38 -0.81; P = 0.03) and patients with polyps (0.64, 0.42-0.86; P = 0.012) . No such differences were seen in the group with polyps compared with controls. Conclusions: These results suggest that changes in the meta bolism and/or absorption of bile acids may occur in patients with esta blished colorectal cancer.