Åberg F et al. (2008) Risk of malignant neoplasms after liver transplantation: a population-based study. Liver Transpl 14: 1428–1436

Transplantation and immunosuppression have been associated with an increased risk of cancer; however, few liver transplantation studies have compared cancer rates between transplant recipients and the general population. In a new study, Åberg et al. reveal that liver transplant recipients are almost three times more likely to develop cancer than the general population.

The team studied 540 Finnish liver transplant recipients (mean age 43 years, 296 females) who received transplants at the Helsinki University Central Hospital between 1982 and 2005, and compared the cohort with the national population register. During 3,222 person-years of follow-up, 39 post-transplant de novo cancers (found in 36 patients) were detected, the most common types being lymphoma (n = 9) and skin cancer (n = 11). Transplant recipients had a standardized incidence ratio for all cancers of 2.59 (95% CI 1.84–3.53) in comparison with the general population; this ratio was markedly elevated for non-Hodgkin lymphoma and nonmelanoma skin cancer 13.9 (95% CI 6.01–27.4) and 38.5 (95% CI 18.5–70.8), respectively. Risk of non-Hodgkin lymphoma was increased in the immediate post-transplant period in male patients and in young transplant recipients. Cases of nonmelanoma skin cancer occurred most frequently in patients who had received antibody induction therapy and older patients.

Åberg and colleagues estimate that one in six liver transplant patients are likely to develop cancer within the 20 years following transplantation. These results highlight the value of post-transplant cancer surveillance, and the importance of developing immunosupressive therapies that might reduce the risk of cancer.