De novo colorectal cancer: five-year survival is markedly lower in transplant recipients compared with the general population.

INTRODUCTION: The biological behavior of most solid tumors in transplant recipients has not been adequately compared to the general population. The purpose of the present study was to compare outcomes in de novo colorectal cancer (CRC) following solid organ transplantation to those observed in the general population (SEER) database.
METHODS: All transplant recipients with de novo CRC in the Israel Penn International Transplant Tumor Registry were identified and analyzed and the data were compared to CRC patients in the SEER National Cancer Institute (NCI) database.
RESULTS: One hundred and fifty transplant recipients with de novo CRC were identified, among which were 93 (62%) kidney, 29 (19.3%) heart, 27 (18%) liver, and 1 (0.7%) lung recipients. Median age of transplant recipients was 54 years, compared to a median age of 72 years for patients in the SEER NCI database. However, compared to patients from the SEER NCI database, recipients with Duke's A through C stage disease were noted to experience a significant decrease in 5-year survival. The results in Duke's C patients were particularly dismal.
CONCLUSIONS: The early age at presentation of CRC in transplant recipients suggests that the development of de novo CRC may be effected by immunosuppression. Decreased 5-year survival rates in transplant recipients compared to the general population suggest that CRC in transplant patients is biologically more aggressive. These data cannot distinguish whether the lower survival rates are because the CRC are inherently biologically more aggressive or whether immunosuppression allows for more aggressive clinical behavior of CRC.