E AU1,2,3, J CHAPMAN2, A TEIXEIRA-PINTO1,3, J CRAIG1,3, G WONG1,2,3
1Centre for Kidney Research, The Children’s Hospital at Westmead, , Sydney, Australia, 2Centre for Transplant and Renal Research, Westmead Hospital, Sydney, Australia, 3School of Public Health, Faculty of Medicine, University of Sydney, Sydney, Australia
Aim: To compare the cancer incidence and mortality rates in transplant recipients during periods of graft function and failure with age- and gender-matched general population.
Background: Kidney transplant recipients experience higher cancer incidence and mortality compared to the general population. It is uncertain whether this increased risk varies with graft function.
Methods: All Australian patients who commenced renal replacement therapy between 1982 and 2014 were included from the ANZDATA Registry. Cancer incidence and mortality for dialysis patients and transplant recipients during periods of graft function and failure were compared with the Australian general population using standardised incidence (SIR) and mortality ratios (SMR).
Results: A total of 47,127 dialysis patients without transplants, 15,413 with 1st transplants, 3,873 after 1st graft failure, 1,596 and 545 with 2nd transplants and 2nd graft failure were identified and followed for 297,626 patient-years. The standardised incidence and mortality rates (per 100,000 patient-years) were 727 and 336 in dialysis patients; 1322 and 675 in recipients with 1st transplants; 1017 and 367 after 1st grafts failed; 1531 and 870 for 2nd transplants and 1434 and 880 after 2nd graft failure. Cancer SIRs (95%CI) and SMRs (95%CI) were 1.2 (1.1-1.2) and 1.3 (1.2-1.4) for dialysis patients; 2.1 (2.0-2.2) and 2.6 (2.4-2.8) for recipients with 1st transplant; 1.6 (1.4-1.9) and 1.4 (1.0-1.9) after 1st grafts failed; 2.4 (2.1-2.9) and 3.4 (2.6-4.2) for 2nd transplants; 2.3 (1.5-3.4) and 3.4 (1.8-5.9) after 2nd graft failure.
Conclusions: An increased cancer and cancer mortality risk is observed during periods with a functioning transplant. Among patients with failed allografts, cancer risk and mortality remained higher than the general population, but the increased risk appears lower than recipients with functioning grafts.
Eric Au is a nephrologist and a PhD student at the University of Sydney.