Korean J Transplant.  2023 Nov;37(Suppl 1):S101. 10.4285/ATW2023.F-6825.

Association of human leukocyte antigen homozygosity and de novo malignancies in kidney transplant recipients

• Kang M
• Koh H
• Yim SH
• Choi MC
• Kim HJ
• Huh KH
• Lee J
• Kim MS

• KMID: 2551721
• DOI: http://doi.org/10.4285/ATW2023.F-6825

Abstract

Background
Human leukocyte antigen (HLA) plays a crucial role in the immune response through antigen recognition. Homozygosity at HLA loci may lead to reduced immunosurveillance and an increased risk of malignancy. However, the impact of HLA diversity on de novo malignancy in kidney transplant recipients has not been thoroughly assessed.
Methods
We conducted a retrospective analysis of 2,157 adult kidney transplant recipients who underwent transplantation at Severance Hospital between 2006 and 2020. To address the diverse timeframes for malignancy occurrence after transplanta-tion, we employed a nested case-control study design. The de novo malignancy group patients were carefully matched with the control group in a 1:3 ratio, considering both the year of transplantation and the malignancy index date.
Results
During a median follow-up of 99 months, a total of 184 patients were diagnosed with de novo malignancy after kidney transplantation. The de novo malignancy group exhibited significantly lower patient survival compared to the control group. However, there was no significant difference in death-censored graft survival between the two groups. Our multivariable anal-ysis confirmed that HLA-B homozygosity was independently associated with de novo malignancy (odds ratio, 2.08; 95% confidence interval, 1.14–3.70; P=0.015). Furthermore, recipient older age, deceased donor kidney transplant, higher body mass index, hepatitis B virus carrier status, and a history of pretransplant malignancy were identified as independent risk factors for de novo malignancy.
Conclusions
Our findings suggest that HLA-B homozygosity is associated with an increased risk of de novo malignancies after kidney transplantation.