De novo malignancies after renal transplantation--a single-center experience in the Balkans.

The occurrence of malignancies is a well-known serious complication after organ transplantation. Despite the fact that many factors may be involved, the pathogenesis is still unclear. The aim of the present study was to examine the incidence and clinical characteristics of de novo malignancies that arise after renal transplantation over a 13-year experience in a single center in the Balkan Peninsula. During this period, 185 renal transplantations (139 living related and 46 cadaveric) were followed in our department. Overall, 19 malignancies (9.78%) were observed in 15 patients (7.8%). The mean age of these patients was 45 years (range, 21-53 years). Ten patients (55%) developed skin cancers: 8 squamous and 2 basal cell. Kaposi's sarcomas were found in 3 patients (16.6%, 1 visceral form). We also detected 1 breast cancer, 1 seminoma, 1 colon cancer, 1 urogenital-transitional cell-like cancer, 1 renal cell carcinoma, 1 plasmacytoma, and 1 retroperitoneal sarcoma after an ABO incompatible transplantation. All cancers were de novo malignancies that presented at a mean time of 21 months (range, 2-52 months) after surgery. In conclusion, the incidence of malignancy in the present series was similar to that reported elsewhere. The predominance of skin cancers was understandable bearing in mind the sunshine. The appearance of skin malignancies in our group of patients was earlier, more severe, and multiple sites. No cases of posttransplantation lymphoproliferative disorders were observed. Careful clinical examination and long-term screening protocols are needed for early detection and treatment of this life-threatening complication among the transplant population.