Duration and severity of primary sclerosing cholangitis is not associated with risk of neoplastic changes in the colon in patients with ulcerative colitis.

BACKGROUND: Annual surveillance colonoscopy to detect colon cancer is recommended for patients with primary sclerosing cholangitis (PSC) and ulcerative colitis (UC). Limited data currently support these recommendations.

OBJECTIVE: To study whether a relationship exists between the severity and duration of PSC and the risk of colon cancer and dysplasia (colon neoplasia).

DESIGN: Retrospective, longitudinal study.

SETTING: Tertiary-care referral center.

PATIENTS: Information pertaining to duration of PSC, UC, requirement for orthotopic liver transplantation, and time to diagnosis of colon neoplasia was obtained for patients with PSC and UC. Patients were evaluated and followed-up from 1985 to 2011 at a single institution.

MAIN OUTCOME MEASUREMENTS: Association between the severity and duration of PSC-UC and the time of occurrence of colon neoplasia.

RESULTS: Of 167 patients with a combined diagnosis of PSC-UC, 55 had colonic neoplasia on colonoscopy. Colonic neoplasia occurred more frequently within 2 years of a combined diagnosis of PSC-UC (6.6/100 patient-years of follow-up) than after 8 years from PSC-UC (2.7/100 patient-years of follow-up). On proportional hazards analysis, older age at PSC diagnosis (hazard ratio 1.23 for every 5 years; 95% confidence interval, 1.03-1.34; P = .014) increased the risk of colon neoplasia.

LIMITATIONS: Retrospective study.

CONCLUSION: In this study, the severity of PSC was not significantly associated with the risk of colon neoplasia. Patients with PSC and UC have a high risk of colon neoplasia soon after the coexistence of the two diseases is discovered. Older age at PSC diagnosis increases this risk.