Purpose: Most patients with primary sclerosing cholangitis also have ulcerative colitis. It has been suggested that in the presence of primary sclerosing cholangitis the risk of colorectal dysplasia and carcinoma is greater than in patients with ulcerative colitis alone.
Methods: In a retrospective study, we evaluated the possibility of colorectal cancer or dysplasia in 35 consecutive patients with primary sclerosing cholangitis and ulcerative colitis seen at The Johns Hopkins Hospital between 1979 and 1991.
Results: Thirteen of the 35 patients (37 percent) with ulcerative colitis and primary sclerosing cholangitis had colorectal neoplasia (5 with adenocarcinoma and 8 with dysplasia). In the 27 patients undergoing colonoscopic biopsy surveillance, the cumulative incidence at 28 years of colorectal cancer was 18.5 percent and for colorectal dysplasia it was 29.6 percent. The high incidence of colorectal cancer was less than the rate of colorectal cancer in patients with extensive colitis of childhood onset without primary sclerosing cholangitis (35 percent), but the rate of colorectal cancer and dysplasia (48.1 percent) is similar to the highest rates of cancer noted in the comparison group. Because patients had subtle, quiescent colitis, a short time from diagnosis of ulcerative colitis to diagnosis of colorectal neoplasia was noted (mean, 12.2 +/- 9 years; less than 8 years in 5/13 (38.5 percent) patients).
Conclusion: Ulcerative colitis patients with primary sclerosing cholangitis appear to have a high frequency of colorectal cancer but a rate lower than expected in patients with extensive quiescent ulcerative colitis of childhood onset alone. However, exact conclusions are complicated by the high incidence of colorectal dysplasia found, which portends malignant transformation. Because of the subtle nature of colitis, the diagnosis of ulcerative colitis is often delayed, and surveillance programs should start as soon as ulcerative colitis is diagnosed.