Epstein-Barr Virus Predicts Malignancy After Pediatric Heart Transplant, Induction Therapy and Tacrolimus Don't

Patients after heart transplantation are at increased risk for malignancy secondary to immunosuppression and oncogenic viral infections. Most common among children is posttransplant lymphoproliferative disorder (PTLD), occurring in 5% to 10% of patients. We used a national database to examine the incidence and risk factors for posttransplant malignancy.

The United Network for Organ Sharing database was queried for pediatric (<18 years) heart transplant recipients from October 1987 through November 2019. Freedom from malignancy after transplant was assessed with Kaplan-Meier analysis. Cox regression was performed to generate hazard ratios (HRs) and 95% CIs for risk of malignancy development.

Of 8581 pediatric heart transplant recipients, malignancy developed in 8.1% over median follow-up time of 6.3 years, with PTLD compromising 86.4% of the diagnosed cancers. The incidence of PTLD development was 1.3% at 1 year and 4.5% at 5 years. Older age at the time of transplant was protective against the development of malignancy (HR, 0.98; 95% CI, 0.96-0.99; P < .001), whereas a history of previous malignancy (HR, 1.9; 95% CI, 1.2-3.0; P = .007) and Ebstein-Barr virus (EBV) recipient-donor mismatch (HR, 1.7; 95% CI, 1.3-2.2; P < .001) increased the risk. Induction therapy, used in 78.9% of the cohort, did not increase malignancy risk (P = .355) nor did use of maintenance tacrolimus (P = .912).

PTLD occurred after 7% of pediatric heart transplants, with risk increased by younger age and EBV mismatch, highlighting the importance of PTLD monitoring in EBV-seronegative recipients. Induction therapy, used in most of the pediatric heart transplants, does not seem to increase posttransplant malignancy nor does tacrolimus, the most commonly used calcineurin inhibitor.