Increased colorectal neoplasia in chronic ulcerative colitis complicated by primary sclerosing cholangitis: fact or fiction?

It is well accepted that patients with ulcerative colitis (UC) are at increased risk of developing colorectal carcinoma. Since 1992, several studies have examined the hypothesis that patients with concomitant primary sclerosing cholangitis (PSC) are at significantly increased risk of developing colorectal cancer or dysplasia. The size, design, end points, and populations involved in these studies have varied but critical review suggests that colorectal cancer is more common in the setting of PSC. Although the data do not allow exact quantification of the increased relative risk, there are nevertheless implications, both for understanding disease pathogenesis and for clinical practice.