Background: Increasing time on dialysis is an established risk factor for certain cancer types for patients on dialysis, but the relationship between the time on dialysis and cancer risk after transplantation is unclear. We aimed to determine if the length of time on maintenance dialysis before the first kidney transplantation was associated with the risk of site-specific and overall incident cancers after transplantation.
Methods: Using the Australia and New Zealand Dialysis and Transplant Registry, we assessed the association between both all cancers (except for nonmelanocytic skin cancers) and site-specific cancer incidence and the duration on dialysis before the first transplantation using adjusted Cox proportional hazards and competing risk models.
Results: Over a median follow-up of 4.4 years (interquartile range, 1.7–7.7 years), the total cumulative incidence of all cancers after the first kidney transplantation was 15.0 per 1000 patient-years. There was a linear relationship between the duration of dialysis and the risk of cancer after transplantation (Ptrend=0.02). The excess risks for lung and urinary tract cancers were highest among recipients who had been on dialysis for the longest duration before transplantation (adjusted hazard ratio [95% confidence interval], 3.32 [1.00–11.4]; P=0.05 and 2.57 [1.33–4.95]; P=0.005, respectively).
Conclusion: Increasing time on dialysis is a significant risk factor for common solid organ cancers, such as lung cancer, and urinary tract cancers in kidney transplant recipients, irrespective of age. Strategies to improve cancer surveillance among recipients who had been on dialysis for a longer time may be warranted.
1 Sydney School of Public Health, University of Sydney, Sydney, New South Wales, Australia.
2 Centre for Kidney Research, The Children’s Hospital at Westmead, Westmead, New South Wales, Australia.
3 Centre for Transplant and Renal Research, Westmead Hospital, Westmead, New South Wales, Australia.
4 Department of Renal Medicine, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia.
5 Address correspondence to: Germaine Wong, M.B.B.S., M.Med.(Clin. Epi.), Ph.D., F.R.A.C.P., Centre for Transplant and Renal Research, Westmead Hospital, Westmead, New South Wales 2145, Australia.
The authors declare no funding or conflicts of interest.
G.W. designed and performed the research, analyzed the data, and wrote the article. R.M.T. performed the research, analyzed the data, and contributed to the writing of the article. J.R.C. and J.C.C. advised on the performance of the research and data analysis and contributed to the writing of article. M.H., W.H.L., and A.C.W. advised on the performance of the research and revised the article.
Received 30 July 2012. Revision requested 16 September 2012.
Accepted 2 October 2012.