Background and PurposeLiver transplantation (LT) is the treatment of choice for end-stage liver disease. These patients are at increased risk for developing malignancies due to the required immunosuppression. Some viruses play a crucial role. Data on neoplasms of the colon, rectum and anus in LT are limited. The aim of this retrospective study was to analyze the incidence and clinical course of colorectal and anal malignancies and colonic polyps in a series of patients who underwent LT at a single institution.MethodsA retrospective evaluation was performed for 467 consecutive LTs in 402 individuals between 1998 and 2001. Standard immunosuppression consisted of Tacrolimus, Mycophenolic acid and steroids.ResultsDuring a median follow up of 5.2 years, three colon adenocarcinomas, one cecal post-transplant lymphoproliferative tumor, and two anal tumors were identified. Posttransplant adenomatous polyps were detected in 47.3% of patients with pretransplant polyps versus 6.7% of patients without pretransplant polyps (p<.001). These incidences of metachronous and new polyp formation are similar to people who are not immunocompromised. Patients transplanted for alcoholic liver disease (ALD) had a significantly higher rate of adenoma formation (50.0% vs 11.1%, p<.001). ConclusionsThe lack of increased risk of metachronous colonic polyps and new polyp development in post LT patients suggests that immunosuppression does not predispose patients to polyp formation. However, patients transplanted for ALD appear to be at particular risk for adenomatous polyp formation. An increased incidence of post LT viral-associated malignancies, including PTLD and anal cancer, suggests that complete screening of the colon, rectum, and anus must be utilized for this patient population.