Clinical implications from a single-center study of colorectal adenocarcinoma in transplant recipients

Background: With the increasing burden of organ transplant recipients and improvements in allograft outcome, the incidence of neoplasms rising from these patients is an important issue. Objective: In this study, we investigated transplant recipients with colorectal cancer to determine its incidence, clinicopathological characteristics, and prognosis. Methods: The database of Severance Hospital was queried for all cases of colorectal adenocarcinoma among transplant recipients from August 2005 to January 2013. Results: A total of 29 patients were diagnosed with colorectal adenocarcinoma after transplantation, and the median age at diagnosis was 58.6 years. As for primary tumor stage, 17 (58.6%) patients had stage ≥3, and distant metastasis was found in 10 (34.4%) patients. The mean time from transplantation to tumor detection was 13.7 years. The median disease-free survival was 11.0 months and the median overall survival (OS) was 18.1 months. In multivariate analysis of prognostic factors for OS, surgical resection was a positive prognostic factor (HR 1.357, p = 0.010) and the presence of distant metastasis at diagnosis was a negative prognostic factor (HR 1.047, p = 0.006). Conclusion: The behavior of colorectal cancer in posttransplant patients is more aggressive and refractory to treatment. A separate guideline for the colorectal screening program for the posttransplant patients needs to be established.