Donor-derived urologic cancers after renal transplantation: A retrospective non-randomized scientific analysis

BACKGROUND: Malignancies in the urinary tract and the kidney graft are quite common after kidney transplantation. In some selected cases tumours develop from donor-derived tissue. OBJECTIVES: We hypothesised that there is a clinical value to investigate donor/recipient origin in urologic malignancies in renal transplant recipients. METHODS: In this retrospective study, including patients transplanted between the years 1969 and 2014 at Uppsala University Hospital, Sweden, 11 patients with malignancies in urinary tract and 4 patients with malignancies in kidney transplants were investigated. Donor/recipient origin of tumour tissue was analysed by polymerase chain reaction (PCR) of human leucocyte antigen (HLA) genotypes or by fluorescence in situ hybridization (FISH analysis) of sex chromosomes. HLA genotype and sex chromosomes of the tumour were compared to the known HLA genotype and sex chromosomes of recipient and donor. RESULTS: Three of ten cancers in the urinary tract and three of four cancers in the kidney transplants were donor-derived. CONCLUSIONS: We suggest that urologic malignancies in renal transplant recipients can be investigated for transplant origin. In addition to conventional therapy the allograft immune response against these tumours can be valuable to treat donor-derived cancers.