Background: Posttransplant lymphoproliferative disorders (PTLD) are a common malignancy after renal transplantation with a high incidence of PTLD described in the first posttransplant year. We sought to determine incidence and risk determinants of PTLD in Irish kidney transplant recipients.
Methods: Retrospective observational study of 1996 adult first kidney transplant recipients between 1991 and 2010 in the Republic of Ireland. Recipients were cross-referenced with the National Cancer Registry to determine incidence of PTLD. Kaplan-Meier analysis was performed for PTLD-free survival, allograft survival, and patient survival after PTLD. Cox proportional hazards models were used to identify independent risk factors for PTLD in our population.
Results: We identified 31 cases of PTLD during the study period. Histological subgroups included: early lesions (n = 1); polymorphic PTLD (n = 1); monomorphic PTLD (n = 27), Hodgkin disease (n = 2). Median time to PTLD diagnosis was 8.3 (range, 1.2-13.9) years. Cumulative incidence (95% CI) of PTLD at 1, 2, 3, 5, 10, and 15 years was 0%, 0.16% (0.05-0.5%), 0.21% (0.08-0.57%), 0.21% (0.08-0.57%), 1.76% (1.15-2.69%), and 3.07% (2.1-4.43%), respectively. Allograft survival after PTLD diagnosis was 94.4% (66.6-99.2%) at 5 years. Patient survival after PTLD diagnosis was 64% at 1 year, 53% at 2 years, 48% at 5 years, and 37% at 10 years. No risk factors for PTLD were identified.
Conclusions: We found a paucity of early onset PTLD in our cohort with no cases in the first posttransplant year. Potential contributing factors included a high prevalence of previous Epstein-Barr virus exposure and a relatively low immunological risk profile in our recipient cohort compared with prior studies. Further studies are required to reevaluate the epidemiology of PTLD in the modern era of transplant immunosuppression.
The authors reveal incidence and risk determinants of posttransplant lymphoproliferative disorders in Irish kidney transplant recipients as a national observational study. In their cohort, there is a paucity of early onset disease with no cases in the first year posttransplant.
1 Department of Nephrology and Transplantation, Beaumont Hospital, Dublin, Ireland.
2 Department of Pathology, Beaumont Hospital, Dublin, Ireland.
3 National Cancer Registry Ireland, Cork, Ireland.
Received 17 September 2015. Revision received 20 February 2016.
Accepted 23 February 2016.
The authors declare no funding or conflicts of interest.
J.A.O.R. participated in the study design, data collection. S.P. participated in study design and pathology data collection. J.A.M.C. participated in study design. C.T, is a co-author. F.J.O.B., F.L.W., D.O.D., C.K., E.B. and S.K. participated in data collection. Y.W. is from the National Renal Transplant Registry. P.O.K. is a statistician. S.D. is from the National Cancer Registry Ireland. H.C. is the Director of National Cancer Registry Ireland. M.L. is the lead investigator and participated in pathology. P.J.C. is the lead investigator and participated in nephrology and transplantation.
Correspondence: John A. O'Regan, MD, Nephrology and Transplantation Department, Beaumont Hospital, Dublin 9, Ireland. (firstname.lastname@example.org).