Abstract
Ewing sarcoma (ES) is a rare group of undifferentiated tumors that originate from neuroectoderm. Although the overall prognosis is poor, early diagnosis and treatment by a multidisciplinary team with multimodal therapy can improve outcomes. Therefore, we present a 22-year-old female patient with primary renal ES with tumor thrombosis up to the vena cava who had radical nephrectomy and IVC tumor thrombectomy followed by adjuvant chemotherapy because a preoperative percutaneous biopsy was confirmed the diagnosis.