Background: Patients with PSC and IBD have a high incidence of colonic carcinomas (CRC), and the annual incidence of CRC increases with duration of disease. UDCA treatment has been suggested to reduce colonic dysplasias and carcinomas.
Aims: The annual incidence of colorectal carcinomas after long-term UDCA treatment was studied.
Methods: Patients included in a prospective study on the outcome after ursodeoxycholic acid (UDCA) treatment were evaluated.
Results: A total of 120 of 171 PSC patients included had IBD (108 UC and 12 CD). All patients were treated with UDCA for a median time of 6.7 years. Seven patients with PSC and IBD developed a CRC yielding a prevalence of 5.8%. In years 0-3 (n = 120) after the start of UDCA, the annual incidence rate of CRC was 0.62/100 patient years; in years 3-6 (n = 93) it increased to 1.28 and decreased thereafter in years 6-9 (n = 67) to 1.17, then in years 9-12 (n = 42) to 0 and after >12 years (n = 24) it remained 0. In PSC with IBD, Kaplan-Meier estimate of CRC formation increased with time in the first years of treatment and reached a plateau after 9 years; after treatment for ≥ 9 years, no further CRC were observed.
Conclusion: After the start of UDCA, the annual incidence of CRC increased up to 6 years and subsequently decreased. In PSC with IBD treated with UDCA, most colonic carcinomas develop in the first years after the start of treatment.