CASE REPORT   

Journal of Radiological Review 2020 July-August;7(4):307-12

DOI: 10.23736/S2723-9284.20.00257-5

Copyright © 2020 EDIZIONI MINERVA MEDICA

language: English, Italian

Primary Ewing sarcoma of the kidney associated with retroperitoneal hematoma and renal vein thrombosis

Giovanni STAMATI ¹ ✉, Maria ROSIGNUOLO ¹, Stefano GIUSTI ¹, Francesco PATA ^{2, 3}

¹ Department of Radiology, Spoke Center, Corigliano-Rossano, Cosenza, Italy; ² General Surgery Unit, Department of Surgery, Nicola Giannettasio Hospital, Corigliano-Rossano, Cosenza, Italy; ³ La Sapienza University, Rome, Italy

Ewing Sarcoma (ES) of the kidney, belonging to the Ewing Sarcoma Family Tumors (ESFTs), is a rare malignancy of neuroectodermal origin, representing less than 1% of all renal tumors. Compared to ES in other locations, renal ES usually arises in young adults with a slight male predominance and worse prognosis. Here we present the case of a 51-year-old man with a 3-day history of right flank pain, fever and macrohematuria. Abdominal ultrasound showed a large ill-defined heterogeneous mass, hypoechoic to renal parenchyma with necrotic areas, in the upper pole of the right kidney. The multiphase abdominal CT scan confirms presence of a 7.7×7.1×7.4 cm hypovascular right upper pole renal mass with internal necrosis, a large perirenal hematoma and renal vein thrombosis. No metastases were detected. The patient underwent open right radical nephrectomy. Histopathology of the resected tumor revealed features of ES of the kidney which was confirmed by fluorescence in-situ hybridization technique and molecular test for the EWSR1 gene. The radiological features of renal ES are not specific. Renal ES mostly present with nonspecific symptoms, such hematuria and abdominal pain, and it is more frequently metastatic at the time of diagnosis. A definitive diagnosis of ES usually results from a combination of histopathological, immunohistochemical and molecular criteria. To date, over one hundred cases have been reported in the literature. Although rare, ES should be considered in the differential diagnosis of any renal mass. Due to its aggressive behavior and high metastatic potential, a prompt diagnosis is needed to initiate the appropriate therapy.

KEY WORDS: Ewing sarcoma; Kidney neoplasms; Retroperitoneal space; Human EWSR1 protein; Renal veins; Thrombosis