Abstract

Background: Multimodal treatment for pediatric liver tumors, including indications for transplantation, has evolved over the last several decades. The main objective of this study was to describe the outcomes following liver transplantation (LT) for children with primary hepatic malignancies over 30 years at our center which has the largest pediatric LT program in Canada.

Methods: Charts of patients transplanted at our center for primary hepatic tumors between January 1990 and December 2021 were included in our retrospective review. Demographic, operative, and outcome data were collected. Chi-square tests and univariate analyses were performed for survived vs non survived patients with hepatoblastoma. A p value of ≤0.05 was considered significant.

Results: A total of 37 patients underwent LT for primary hepatic malignancies during the study period: 31 hepatoblastoma (HB) and 6 non-HB (2 hepatocellular carcinoma (HCC), 2 undifferentiated embryonal sarcoma, 1 angiosarcoma and 1 multifocal infantile hemangioma). In HB patients with available data (14 females, median age at diagnosis 29.5 months; range 1-158), 2 (7.4%) were PRETEXT II, 8 (29.6%) and 16 (59.3%) were PRETEXT III and IV, respectively. Metastases at diagnosis were detected in 4 (13.3%) patients, all in the lungs. Of these, 1 patient had a residual lesion which was decreasing rapidly in size. All the patients received neo-adjuvant chemotherapy (median cycles- 6; range 2-10), while 14/25 had adjuvant chemotherapy. The median age at transplant was 34 months (range 6-160). One (3.2%) patient had salvage transplant secondary to incomplete tumor resection. Overall survival was 74.2% (23/31) with a median follow-up of 132 months (range 1-355). All deaths were secondary to disease recurrence (median 15 months after LT; range 1-78). The most common site of recurrence was lungs (62.5%). Higher median alpha-fetoprotein (AFP) prior to LT was associated with worse survival (160296 vs 848 µg/L; p 0.003). AFP decrease of >95% from presentation was significantly associated with improved survival (p 0.024). Other factors such as tumor histology, AFP at diagnosis, PRETEXT/POSTEXT stage, metastasis at diagnosis, liver donor type and era of LT, or positive resection margin (R1) were not associated with differences in survival in our cohort. All the non-HB recipients were alive following LT at the last visit (median 9.5 months, range 1-51). None had extrahepatic disease at presentation. Recurrence of disease was noted in 2 patients (1 HCC and 1 angiosarcoma), each treated with surgical resection.

Conclusion: The overall survival rate following liver transplant in HB patient is 74.2%, with tumor recurrence as the most important contributor of mortality. Lower AFP levels before LT and >95% AFP decrease from presentation are associated with survival. LT in non-HB tumor has favorable outcomes in selected patients, even with post-transplant recurrence.