De novo malignancies in renal transplant recipients: experience at a single center with 1882 transplant patients over 39 yr

Purpose Cancers complicating organ allografts are a major cause of morbidity and mortality after renal transplantation. Different registries have described an overall three to eightfold increase in cancer risk compared with the general population. This retrospective study investigated the incidence and outcome of de novo malignancies following kidney transplantation in a single German kidney transplantation center. Materials and Methods Between 1966 and 2005, 1882 patients underwent kidney transplantation at the ErlangenNuremberg kidney transplantation center. The incidence and types of post-transplant malignancies were retrospectively analyzed according to the patients' records and the database of the local cancer registry. Results We identified 257 malignancies in 231 patients, an overall incidence of 13.7%. The mean follow-up time was 9.9 yr (range, 0.4-25.5 yr). The observed incidence data corresponded to a 12.1-fold increase in the overall risk of developing a malignant nonskin tumor compared with the nontransplanted population. Urinary tract malignancies represented the most frequent malignancies among the nonskin tumors (32.1%), followed by gastrointestinal tract (30.7%) and gynecological (14%) cancers. When we considered the duration from renal transplantation to tumor detection and tumor-specific survival, there was no difference between patients treated with or without a cyclosporine A-based regimen. Conclusions In our study, the overall risk of developing a post-transplant nonskin malignancy was 12.1-fold higher compared with the age-matched general population. Development of solid organ malignancies is one of the most frequent causes of morbidity and mortality in renal transplant recipients; thus, close tumor screening in patients after kidney transplantations is warranted.