Variations in risk of cancer and death from cancer according to kidney allograft function, graft loss, and return to dialysis

Abstract

BACKGROUND: Cancer incidence and mortality may change with varying kidney allograft function and after graft loss. We aimed to quantify cancer incidence and mortality during periods with a functioning graft and after graft loss. Methods: We included all adult Australians aged 20 and above who commenced kidney replacement therapy between 1982 and 2014 using data from Australia and New Zealand Dialysis and Transplant Registry. We calculated the standardized incidence ratios and standardized mortality ratios (standardized against the Australian general population) for dialysis patients and transplant recipients during periods with a functioning graft and after graft loss. Results: A total of 44 765 dialysis patients without transplants, 13 443 with first kidney transplants, 2951 after first graft loss, 1010 with second transplants, and 279 after second graft loss were followed for 274 660 patient-years. Cancer incidence and mortality (per 100 000 patient-years) were 1564 and 760 in dialysis patients, 1564 and 689 in recipients of first transplants, 1188 and 390 after first graft loss, 1525 and 693 after second transplants, and 1645 and 779 after second graft loss. Cancer standardized incidence ratios and standardized mortality ratios (95% confidence intervals) were 1.15 (1.11-1.20) and 1.29 (1.21-1.36) for dialysis patients, 2.03 (1.94-2.13) and 2.50 (2.33-2.69) for recipients following their first transplant, 1.55 (1.29-1.85) and 1.40 (1.00-1.90) after first graft loss, 2.18 (1.79-2.63) and 3.00 (2.23-3.96) for second transplants, 2.59 (1.56-4.04) and 3.82 (1.75-7.25) after second graft loss. Conclusions: In kidney transplant recipients, cancer incidence and mortality are highest during periods with a functioning graft and remained higher than in the general population even after graft loss.