Transplanting People with a Prior History of Cancer: An Analysis of the Australian and New Zealand Dialysis and Transplant (ANZDATA) Registry

Abstract

Introduction: Deciding whether kidney transplantation is feasible and safe for people with prior cancer is challenging, and the optimum waiting time from cancer diagnosis to transplantation is not clear. We aimed to describe characteristics, waiting intervals and outcomes of people with prior cancer who underwent kidney transplantation in Australia and New Zealand. Methods: Using ANZDATA we described characteristics of adults (>20years) with cancer (excluding non-melanoma skin cancer), prior to ESKD. We estimated waiting time to transplantation and survival outcome for people with all-site and breast, melanoma, bladder, kidney and colorectal cancers and compared this to those without prior cancer history using the Cox proportional hazards model. Results are expressed as hazard ratios (HR) with 95%confidence intervals (CI) Results: 15,440 adults received kidney transplants between1963-2007, and 384 (2.5%) had at least one cancer before transplantation. Median follow-up was 14.6 years (IQR: 8.5-22.6 years), representing a total of 171,129 person-years of observation. At the end of the study period, 6,940 (44.9%) patients had died, 8,358 (54.1%) were alive and 142 (0.9%) were lost to follow-up. Compared to those without prior cancer, prior cancer recipients were older (50.0% vs. 22.0% aged >=55; p< .001) and less likely to have ESKD due to diabetes or glomerulonephritis (p=0.004), and more likely to have been transplanted in more recent years (p< .001). Of prior cancer recipients, 272 (70.8%) had cancer before starting dialysis and 112 (29.2%) had cancer during dialysis treatment. Median time from cancer diagnosis to transplantation was 5.6yrs, but differed by cancer site (see table). Prior cancer patients had reduced survival (median 14.4 vs.18.1yrs, p=0.01) and graft survival (5.1 vs. 5.5yrs, p=0.02), but these also differed by site. Risk of early death was highest for those transplanted sooner after cancer diagnosis (adjusted HR 1.25, CI 1.01-1.55 within 0-5 years of cancer diagnosis), and for those with bladder (HR 2.33, CI 1.40-3.88), melanoma (HR 1.68, CI 1.01-2.79) and kidney cancer (HR 1.62, CI 1.18-2.23). Prior breast cancer (HR 0.87, 95% CI 0.54-1.39) and colorectal cancer (HR 1.30, 95% CI 0.85-1.97) were not significantly associated with earlier death. Cause of death was recurrence of their prior cancer in 18 (10.3%), new incident post-transplant cancer in 36 (24.5%), cardiovascular events in 67 (38.5%), infection in 24 (13.7%), and other in 29 (16.6%)Table: [Wait time and survival for recipients with prior c]Conclusions: Prior cancer site determines wait-time and post-transplant survival reduced for most people with prior cancer, but risk of death from cardiovascular causes outweighs risk of cancer recurrence. Future work will model the trade off for early transplantation versus remaining on dialysis for these patients.