Retroperitoneal Extraosseous Ewing’s Sarcoma in a Young Infant: A Case Report and Literature Review

Abstract

Ewing's sarcoma (ES) is a rare malignancy primarily affecting bone and soft tissue in children and adolescents. While often presenting with palpable masses and bone pain, extraskeletal Ewing's sarcoma (EES) can manifest with diverse symptoms depending on the location. Accurate diagnosis and prompt treatment of EES are crucial for minimizing recurrence and improving survival outcomes. This case report describes a young infant presenting with a palpable left-sided abdominal mass, ultimately diagnosed as retroperitoneal EES. An initial computed tomography (CT) scan of the abdomen revealed a necrotic mass on the left side, arising from the pancreatic body and tail, leading to a suspicion of pancreatoblastoma. An unexpected finding during surgical exploration revealed a large, well-circumscribed, yellowish, hypervascular retroperitoneal mass attached to the tail of the pancreas. Histopathological examination of the resected tumor confirmed the diagnosis of Ewing's sarcoma. The infant was subsequently treated with a combination of chemotherapy and radiation therapy due to a tumor attached to the tail of the pancreas. This report highlights the diagnostic challenges and management strategies for retroperitoneal EES in infants, contributing to the limited existing literature on this rare clinical entity.