Complete pathological response of a primary renal Ewing sarcoma to neoadjuvant chemotherapy: A case report.

Primary renal Ewing sarcoma (PRES) is an exceptionally rare and aggressive malignancy with a poor prognosis. The optimal management strategy remains poorly defined due to its rarity. We report a case of a 39-year-old female with PRES. The patient received six cycles of neoadjuvant chemotherapy (VDC/IE regimen), followed by right radical nephrectomy. Histopathological examination revealed dense fibrocollagenous and inflammatory tissue with no viable tumor cells, confirming a pathological complete response (pCR). This case highlights the critical importance of a multimodal treatment approach integrating neoadjuvant chemotherapy and surgery.