In patients with ulcerative colitis (UC) and primary sclerosing cholangitis (PSC) who receive liver transplantation, the risk of colorectal neoplasia and utility of surveillance are not known. In this retrospective study, 81 patients with UC and PSC, 57 of whom had intact colons were followed for a mean of 4 years. Cancer developed in 3 (5%), approximately 1% per person per year. Cumulative incidence of dysplasia was 15% at 5 years and 21% at 8 years. Survival was not affected by an approximate fourfold increase in cancer risk post-transplant when compared to expected risk pretransplant. Prophylactic colectomy does not seem indicated but annual surveillance colonoscopy is recommended.