The Diagnostic Quandary of Primary Renal Ewing's Sarcoma on 18F-FDG PET/CT Scan: A Case Report with a Thorough Review of Literature

Abstract

Ewing's sarcoma (EWS) of the kidney is an extremely rare and aggressive malignancy, accounting for less than 1% of renal tumors. This report presents a 42-year-old male who initially presented with hematuria and intermittent fever, with imaging studies suggesting a renal cell carcinoma (RCC). However, histopathological and immunohistochemical analysis, including CD99 positivity and NKX2.2 nuclear expression, confirmed the diagnosis of primary renal EWS. The patient was promptly started on neoadjuvant chemotherapy (VAC + IE [vincristine, adriamycin, cyclophosphamide, ifosfamide, and etoposide]), which he tolerated well without significant adverse effects. Given its nonspecific clinical and 18F-fluorodeoxyglucose positron emission tomography/computed tomography scan presentation, the case highlights the diagnostic challenges in distinguishing renal EWS from more common renal neoplasms such as RCC. Early diagnosis through histopathology and immunohistochemistry is crucial for guiding appropriate management. Given the aggressive nature of renal EWS, a multimodal treatment approach involving chemotherapy followed by radical nephrectomy is essential for improving prognosis. This case sheds light on the importance of considering renal EWS in the differential diagnosis of renal masses and emphasizes the role of early intervention in enhancing survival outcomes.

Keywords

18F-FDG PET/CT scan - Ewing's sarcoma - kidney - renal neoplasms - small round cell sarcoma

Informed Consent

Written informed consent was taken from the patient to participate in this study and for the publication of any potentially identifiable images or data included in this article. Ethical review and approval are not required, and a waiver for the publication of case reports is provided as per institutional requirements.

PLACE OF STUDY: Department of Pathology, Vardhman Mahavir Medical College And Safdarjung Hospital, New Delhi – 110029, India.

Publikationsverlauf

Artikel online veröffentlicht:
21. Juli 2025

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