Background: To assess the risk and identify risk factors of Hodgkin lymphoma (HL) in solid organ transplant recipients. Prior research has been limited by the rarity of HL and the requirement for extended follow-up after transplantation.
Methods: Using data from the Scientific Registry of Transplant Recipients (SRTR), we conducted a retrospective cohort study of US solid organ transplant recipients (1997-2007). We estimated hazard ratios (HRs) for HL risk factors using proportional hazards regression. Standardized incidence ratios (SIRs) compared HL risk in the transplant cohort with the general population.
Results: The cohort included 283,190 transplant recipients (average follow-up: 3.7 years after transplantation). Based on 73 cases, HL risk factors included male gender (HR: 2.1, 95% CI: 1.2-3.7), young age (4.0, 2.3-6.8), and Epstein-Barr virus (EBV) seronegativity at the time of transplantation (3.1, 1.2-8.1). Among tumors with EBV status information, 79% were EBV positive, including all tumors in recipients who were initially seronegative. Overall, HL risk was higher than in the general population (SIR: 2.2) and increased monotonically over time after transplantation (SIR: 4.1 at 8-10 years posttransplant). Excess HL risk was especially high after heart and/or lung transplantation (SIR: 3.2).
Conclusion: HL is a late complication of solid organ transplantation. The high HL risk in recipients who were young or EBV seronegative at the time of transplant and the fact that most HL tumors were EBV positive highlight the role of primary EBV infection and poor immune control of this virus. The occurrence of HL may rise with improved long-term survival in transplant recipients.