#6346 CANCER RELATIVE SURVIVAL IN DIALYSIS AND KIDNEY TRANSPLANT RECIPIENTS: A POPULATION-BASED STUDY IN AUSTRALIA AND NEW ZEALAND 1980-2019

Abstract

Abstract Background and Aims Cancer survival in the general population has improved over time. Kidney failure population have a higher incidence of cancer with increased mortality. Relative survival following cancer diagnosis can provide more insight into the excess mortality directly or indirectly attributed to cancer in the kidney failure population. Method We estimated and compared the relative survival for dialysis patients, kidney transplant recipients and general population with cancer in Australia and New Zealand from 1980 to 2019. The general population was reference group for background mortality, matching on sex, age, calendar year and country. We used Poisson regression to quantify the excess mortality between these three groups with cancer. Results We included 4,089 dialysis patients and 3,253 kidney transplant recipients with an incident cancer. Dialysis patients were older, had a higher proportion of indigenous people and had more comorbidities than kidney transplant recipients. The kidney failure population had lower 5-year relative survival: 0.25 (95%CI: 0.23-0.26) for dialysis, 0.55 (95%CI: 0.53-0.57) for kidney transplant and 0.670 (95%CI: 0.669-0.670) in the general population with cancer (Figure 1). At any given time, dialysis patients had a 2.10 times higher adjusted excess mortality compared to the general population with cancer (2.10, 95%CI: 2.02-2.18), whereas kidney transplant recipients had no excess mortality (1.02, 95%CI: 0.97-1.08). Relative survival and excess mortality varied by cancer site: lung had the lowest relative survival rates, while kidney failure population with melanoma, breast and prostate cancers had the highest excess mortality. There were also sex differences: women had greater relative survival. Conclusion Relative survival was lower among the kidney failure population with incident cancer compared to the general population with cancer, for all-site and particularly for melanoma, breast and prostate cancer. Decreased survival may be due to poorer access to, more harm or less efficacy of treatments.