Ewing sarcoma
Pronunciation: YOO-ing sar-KOH-mah
A highly aggressive bone and soft tissue malignancy characterized by small round blue cells, primarily affecting children and young adults.
Full Definition
Ewing sarcoma is a member of the Ewing sarcoma family of tumors (ESFT), which includes peripheral primitive neuroectodermal tumor (pPNET). It is the second most common primary bone tumor in children after osteosarcoma. The tumor is characterized by a pathognomonic chromosomal translocation, most commonly t(11;22)(q24;q12), resulting in EWS-FLI1 fusion protein. Ewing sarcoma can arise in both bone and soft tissue, with a predilection for the diaphyses of long bones and flat bones of the pelvis and chest wall. Treatment consists of multimodal therapy including chemotherapy, surgery, and/or radiation therapy.
Usage
Usage note: Named after James Ewing; ensure proper capitalization and avoid confusion with other small round cell tumors.
In Context
- "Molecular testing confirmed EWS-FLI1 fusion consistent with Ewing sarcoma." — Pathology report
- "The patient with Ewing sarcoma responded well to the VDC/IE chemotherapy regimen." — Treatment summary