Undifferentiated Embryonal Sarcoma

Hanlin L. Wang, MD, PhD

Key Facts

Clinical Issues

6-13% of all primary hepatic tumors in childhood
> 50% occurring from 6-10 years of age
Rarely seen in middle-aged and elderly patients
Improved survival in recent years with combined modality therapy

Microscopic Pathology

Spindled, oval, or stellate tumor cells loosely or compactly distributed in myxoid or fibrous stroma
Marked nuclear pleomorphism and hyperchromasia with frequent multinucleated or bizarre giant cells and brisk mitotic activity
Characteristic PAS-positive, diastase-resistant cytoplasmic and extracellular eosinophilic globules
Immunohistochemical evidence of partial divergent differentiation

Top Differential Diagnoses

Embryonal rhabdomyosarcoma

Gross photograph shows a well-demarcated liver mass with a compressed pseudocapsule. The cut surface is variegated with admixed solid areas and a large area of yellow necrosis