Background & aims: There is an increased risk of colorectal carcinoma (CRC) in patients with longstanding, extensive colonic inflammatory bowel disease (IBD). Primary sclerosing cholangitis, family history of CRC, mucosal dysplasia and DNA-aneuploidy are other risk factors. Recently, results from animal studies have shown that the bile acid ursodeoxycholic acid (UDCA) has a favourable impact on experimentally-induced CRC/neoplasia in rats. The aim of this proof of the concept study was to explore the possible preventive/reverting effects of UDCA in patients with colorectal IBD with existing findings of low grade dysplasia and/or DNA-aneuploidy.
Patients and methods: Nineteen patients (13 UC, 6 CD, median age 43 years) with long-standing, extensive IBD (median duration 21 years), with previous findings of low-grade dysplasia and/or DNA-aneuploidy, were randomized to receive either UDCA (500 mg b.i.d) (n=10) or placebo (n=9) in a controlled, double-blind, two-year study. Colonoscopy with multiple biopsies for histopathology and for DNA-flow cytometry was performed at the start and at six-month intervals during the study period. The primary outcome was the need for colectomy due to progression of dysplasia. Changes in dysplasia and DNA-aneuploidy scores were also assessed.
Results: There were no significant differences in the overall composed score between the two groups, either at study start or during the study period. In the placebo group one patient had a progression of dysplasia into high-grade and one patient developed DALM with low-grade dysplasia; both had a colectomy. In contrast, no UDCA-treated patient had progression of dysplasia.
Conclusion: UDCA may prevent further progression of manifest low-grade dysplasia in colorectal IBD. Prolonged treatment or an increased dose may be needed to fully exploit the chemopreventive properties of this compound.