Abstract
Ewing's sarcoma (ES) is a rare malignant small round-cell tumor that usually arises in bone and only exceptionally originates in visceral organs. We report the case of a 7-year-old boy with primary hepatic ES, the youngest case described to date. Imaging revealed a large, solid hepatic mass with heterogeneous enhancement and extensive local vascular involvement, associated with pulmonary and skeletal metastases. Histology and immunohistochemistry (CD99 +, INI-1 +, NKX2.2 +, Ki-67 ≈ 60%) confirmed the diagnosis. This is the first Moroccan and the seventh case of primary hepatic ES reported in the literature, emphasizing the need to consider this entity in the differential diagnosis of pediatric liver tumors.