Waitlist mortality and post-liver transplant outcomes of pediatric patients with hepatocellular carcinoma and hepatoblastoma in the United States.

Background: Liver transplantation (LT) is offered in cases of advanced disease for both pediatric patients with hepatoblastoma (HBL) and those with hepatocellular carcinoma (HCC). Current United States organ allocation priorities differ between the two groups.

Methods: We retrospectively examined the waitlist and posttransplant outcomes of pediatric LT candidates with HBL and HCC using the United Network for Organ Sharing registry (February 2002 to September 2020).

Results: Six hundred sixty-eight children with HBL and 95 children with HCC listed for first LT were identified. Patients with HBL were younger (p < .001), had lower laboratory Model for End-stage Liver Disease (MELD)/Pediatric End-stage Liver Disease (PELD) scores (p < .001), and had lesser proportion with encephalopathy (p = .01). Patients with HCC had an increased risk of waitlist mortality in univariable (unadjusted subdistribution hazard ratio [sHR] = 4.37, 95% confidence interval [CI], 2.01-9.51, p < .001) and multivariable competing risk regression (adjusted sHR = 3.08, 95% CI 1.13-8.37, p = .03) accounting for age and laboratory MELD/PELD score. Five hundred ninety-five children underwent LT for HBL and 76 for HCC. Patients transplanted for HBL had a significantly higher proportion with status 1B exception (71.3% vs. 7.9%, p < .001). No difference was observed in patient (unadjusted log-rank test, p = .52; adjusted hazard ratio [HR] = 0.77, 95% CI, 0.40-1.48, p = .43) or graft survival (unadjusted log-rank test, p = .93; adjusted HR = 0.74, 95% CI 0.42-1.33, p = .32) between HCC and HBL recipients.

Conclusion: Waitlist mortality for pediatric LT candidates with HCC is significantly higher than for HBL, while posttransplant patient and graft survival are similar. This highlights an opportunity to improve equitable prioritization for children with HCC who may have reduced access to size-appropriate deceased donor organs and less effective bridge-to-transplant therapies.