Pediatric Ewing's Sarcoma/Primitive Neuroectodermal Tumor (ES/PNET) Developed in the Small Intestine: A Case Report / 임상소아혈액종양

ABSTRACT

Ewing sarcoma/primitive neuroectodermal tumors (ES/PNET) are a group of malignant tumors with varying degrees of neuroectodermal differentiation. Although it may develop in any organs, ES/PNET originating from small intestine is exceedingly rare. We experienced a 9-year-old girl presenting with abdominal pain, melena, and iron deficiency anemia. Imaging work-up showed multiple masses in the small bowel and omentum with disseminated peritoneal seeding nodules, indicating lymphoma as the most likely diagnosis. Pathological reports from explorative diagnostic laparoscopic biopsy showed tumors comprising small round cells with CD99 expression and EWS-FLI1 translocation leading to the diagnosis of ES/PNET. Tumor burden decreased gradually during five consecutive cycles of systemic chemotherapy. The patient received segmental resection of jejunum, followed by adjuvant chemotherapy. This is the first pediatric case of ES/PNET found in small intestine in Korea.