I. A. Ziogas1, W. K. Wu1, L. K. Matsuoka1, M. Izzy2, A. K. Pai3, D. J. Benedetti4, S. P. Alexopoulos1 1Vanderbilt University Medical Center, Department Of Surgery, Division Of Hepatobiliary Surgery And Liver Transplantation, Nashville, TN, USA 2Vanderbilt University Medical Center, Department Of Medicine, Division Of Gastroenterology, Hepatology And Nutrition, Nashville, TN, USA 3Vanderbilt University Medical Center, Department Of Pediatrics, D. Brent Polk Division Of Gastroenterology, Hepatology, And Nutrition, Nashville, TN, USA 4Vanderbilt University Medical Center, Department Of Pediatrics, Division Of Hematology-Oncology, Nashville, TN, USA
Introduction: Hepatoblastoma (HBL) and hepatocellular carcinoma (HCC) are the two most common primary pediatric liver malignancies. Although survival after liver transplantation (LT) has been previously described in these children, their waitlist outcomes are unknown. We aimed to compare the clinical characteristics, waitlist outcomes, and post-LT survival between children with HBL and HCC.
Methods: All pediatric (<18 years) patients with HBL or HCC listed for a first isolated LT (not multiorgan) between 02/2002-09/2020 in the United Network for Organ Sharing database were included. Waitlist outcomes were examined using Fine-Gray competing risks regression (main risk/outcome: waitlist mortality defined as death/delisting due to being too sick; competing risk/outcome: LT). Post-LT patient and graft survival were examined using the Kaplan-Meier method, log-rank test, and Cox regression.
Results: A total of 668 children with HBL and 95 children with HCC listed for a first isolated LT were identified. Children with HBL were listed younger than children with HCC (P<0.001), had lower laboratory MELD/PELD scores (P<0.001), and had encephalopathy less often (P=0.01). Children with HCC demonstrated an increased risk of unadjusted waitlist mortality compared to children with HBL (subdistribution hazard ratio [sHR]=4.37, 95%CI, 2.01-9.51, P<0.001; Figure A). This effect persisted in multivariable competing risk regression with children with HCC demonstrating three times higher risk of waitlist mortality compared to children with HBL (adjusted sHR=3.08, 95%CI, 1.13-8.37, P=0.03), when adjusted for age and laboratory MELD/PELD score at listing. A total of 595 children with HBL and 76 children with HCC underwent a first isolated LT. Similar differences were appreciated in clinical characteristics as with the waitlist cohort. 71.3% of the children with HBL had a status 1B exception compared to only 7.9% of the children with HCC (P<0.001). No difference was observed in unadjusted patient (P=0.52; Figure B) and graft survival (P=0.93; Figure C) between HCC and HBL. The 5-year patient and graft survival for HBL versus HCC was 82.0% versus 78.0%, and 75.9% versus 74.7%, respectively. Multivariable Cox regression failed to demonstrate differences in either patient survival (adjusted hazard ratio [HR]=0.77, 95%CI, 0.40-1.48, P=0.43) or graft survival (adjusted HR=0.74, 95%CI, 0.42-1.33, P=0.32) between HCC and HBL, when adjusted for age, laboratory MELD/PELD score at LT, and graft type.
Conclusion: Given the similar post-LT survival outcomes, changes in waitlist prioritization could be considered to mitigate the disparities in waitlist mortality between children with HBL and HCC.
