J. Motter1, K. Jackson1, L. Kucirka1, A. Massie1, J. Garonzik-Wang1, S. Bae1, X. Luo1, B. Orandi2, J. Long1, M. Waldram1, A. Muzaale1, J. Coresh1, D. Segev1 1The Johns Hopkins University School Of Medicine,Baltimore, MD, USA 2University Of Alabama at Birmingham,Birmingham, Alabama, USA
Introduction: Incompatible living donor kidney transplant (ILDKT) recipients require increased immunosuppression compared to compatible living donor kidney transplant (LDKT) recipients in order to facilitate transplantation (via desensitization) and prevent acute rejection. This continued exposure to higher levels of immunosuppression may increase their risk of post-transplant cancer.
Methods: Using USRDS data of Medicare beneficiaries, we compared 3351 LDKT to 423 IKT recipients from 22 US transplant centers between 1999 to 2011. Recipients were determined to have developed post-transplant cancer if they had 1 inpatient (Part A) or ≥2 outpatient claims (Part B) for one of 33 different cancers. We estimated the cumulative incidence of post-transplant cancer using the Kaplan-Meier method, and used weighted Cox regression to determine the risk of developing cancer in ILDKT compared to LDKT recipients, adjusting for recipient and transplant-related factors.
Results: The thee-year cumulative incidence of post-transplant cancer was 1.4% for ILDKT and 2.0% for LDKT recipients. After adjusting for recipient and transplant-related factors, there was no difference in risk of post-transplant cancer among ILDKT vs compatible recipients (weighted hazard ratio: 0.24 0.86 3.14, p=0.8). Additionally, there were no cancer-specific differences in risk for ILDKT compared to LDKT recipients, after adjustment for multiple comparisons.
Conclusion: Despite exposure to higher levels of immunosuppression, ILDKT recipients are not at increased risk of developing a post-transplant cancer. While ILDKT recipients are at increased risk for a variety of post-transplant complications compared to LDKT, cancer does not appear to be one of these. While careful monitoring is warranted, this supports current immunosuppression protocol for ILDKT recipients.
