Liver & intrahepatic bile ducts
Other malignancies
Hepatoblastoma
Author: Deepali Jain, M.D.
Topic Completed: 1 February 2012
Minor changes: 14 October 2020
Copyright: 2002-2021, PathologyOutlines.com, Inc.
PubMed Search: Hepatoblastoma[TI] liver[TI]
See also: Epithelial type Mixed epithelial mesenchymal type
Table of Contents
Definition / general | Staging / staging classifications | Prognostic factors | Treatment | Gross description | Microscopic (histologic) descriptionCite this page: Jain D. Hepatoblastoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/livertumorhepatoblastoma.html. Accessed January 22nd, 2021.
Definition / general
- Malignant liver neoplasm almost exclusively in infants, composed exclusively of immature hepatocytic elements (IARC: 8970 / 3 Hepatoblastoma [Accessed 5 December 2017])
- Most common primary liver tumor in children (50% of liver malignancies in children)
- Existence in adults is controversial (J Hepatol 2012;56:1392)
- Can be congenital; 90% occur by age of 5 years, 70% by age of 2 years; 2/3 male, prevalence of 1 per 120,000 (1 per million children under age 15 years)
- Associated with familial colonic polyposis (APC gene, 500x risk), glycogen storage disease, hemihypertrophy (Beckwith-Wiedemann syndrome), Li-Fraumeni syndrome, low birth weight infants, Simpson-Golabi-Behmel syndrome, trisomy 18, Wilms tumor; not associated with cirrhosis
- Also associated with adenomatoid transformation of Bowman capsular epithelium in kidney
- Metastases to adrenal glands, bone marrow, brain, lung, lymph nodes (regional)
- Variable virilization due to hCG production by multinucleated giant cells
- Laboratory: thrombocytosis (Arch Dis Child 1993;69:171), elevated serum AFP (75%)
- Note: diagnosis difficult on needle biopsy; must sample generously
Staging / staging classifications
Based on Children's Cancer Study Group:
- Stage I: completely resected
- Stage II: microscopic residual disease only
- Stage III: gross residual disease or positive lymph nodes or spilled tumor
- Stage IV: metastases
- Note: can also stage using TNM
Prognostic factors
- Stage, age and sex
- Favorable: presence of osteoid
- Unfavorable: small cell / undifferentiated (Pediatr Blood Cancer 2009;52:328) and macrotrabecular patterns, increased mitotic activity; also AFP level < 100, nuclear beta catenin staining, low p27 / kip1, high cyclin D1, 4q deletions
Treatment
- Preoperative chemotherapy and surgery; resect lung metastases; liver transplant if unresectable
- Long term survival now 60 - 70% with most recurrences detected within 3 years
Gross description
- Usually right lobe
- Usually solid, variegated, tan green, solitary (70%), variable hemorrhage and cysts
- Mean 10 cm (range 3 - 20 cm), well circumscribed; often partially encapsulated
- May be calcified or ossified in prominent mesenchymal component
Microscopic (histologic) description
- Epithelial and mesenchymal elements in varying proportions and at variable stages of differentiation
- Pseudocapsule, canaliculi with bile formation, cords 2 - 3 cells thick with alternating light and dark pattern due to glycogen and fat
- Cells smaller than normal hepatocytes
- Extramedullary hematopoiesis common in fetal and embryonal subtypes
- Usually no pleomorphism, no intranuclear inclusions, no hyaline globules, rare / no tumor giant cells, no mitotic figures and no associated cirrhosis
- Rare rhabdoid cells
