Lymphocyte subsets in renal transplant recipients with de novo genitourinary malignancies

Introduction: The incidence of genitourinary tumors (GUT) in renal transplant recipients (RTR) is higher than in the general population. We previously reported that CD4 lymphocytopenia is associated with a high incidence of skin cancer in RTR. Here, we investigate whether persistent CD4 T cell lymphopenia is associated with GUT occurrence. Patients and Methods: A total of 433 patients were included in this study. All patients underwent annually systematic lymphocyte subset (CD3, CD4, CD8, CD19) determination by flow cytometry. Results and Conclusion: During the follow-up period, 13 patients developed GUT: 6 patients a prostate adenocarcinoma (incidence 0.06%/year) and 7 patients a renal cell carcinoma (incidence 0.07%/ year). The patients with GUT were older than those without. Both groups did not differ in posttransplant duration, dialysis mode and duration, induction regimen, or acute rejection history. No persistent CD4 lymphopenia was observed in the patients with GUT. Although CD4 T cell lymphopenia is associated with skin cancer in long-term RTR, it did not appear to be a risk factor for GUT. This suggests that other factors encountered in the setting of kidney transplantation (e. g., immunosuppressive drugs, end-stage renal failure, etc.) favor the development of GUT in RTR. Copyright (C) 2008 S. Karger AG, Basel.