case_images: PMC9867795_01
case_images: CT scan axial view at presentation. CT scan axial view showing a large hypodense mass in the left kidney (red arrow).. CT: Computed tomography
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case_images: PMC9867795_01_cureus-0015-00000033954-i01.jpg
case_images: FIG1
case_images: Computed tomography (CT) scan imaging with contrast of the abdomen and pelvis showed a large hypodense mass of 8cm diameter in the left kidney and a thrombus in the left renal vein (Figures 1, 2).
case_images: CT scan coronal view at presentation. CT scan coronal view showing left renal vein tumor thrombus (blue arrow) and large renal tumor with 8cm diameter (red arrow).. CT: Computed tomography
case_images: cureus-0015-00000033954-i02.jpg
case_images: PMC9867795_01_cureus-0015-00000033954-i02.jpg
case_images: FIG2
case_images: Computed tomography (CT) scan imaging with contrast of the abdomen and pelvis showed a large hypodense mass of 8cm diameter in the left kidney and a thrombus in the left renal vein (Figures 1, 2).
case_images: Histopathological findings of primary renal synovial sarcoma. Hematoxylin and eosin stain image (40x magnification) showing infiltrative and hypercellular neoplastic proliferation of sheets of small cells (blue arrow).
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case_images: PMC9867795_01_cureus-0015-00000033954-i03.jpg
case_images: FIG3
case_images: Microscopic examination showed a monomorphic population of spindle-shaped cells with scant cytoplasm, mild atypia, and conspicuous mitotic activity, with a fascicular growth pattern and areas of necrosis (Figures 3, 4).
case_images: Histopathological findings of primary renal synovial sarcoma.. Hematoxylin and eosin stain image (10x magnification) showing sheets of small cells with ovoid, vesicular nuclei, closely overlapping each other, with scant amphophilic cytoplasm (blue arrow).
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case_images: PMC9867795_01_cureus-0015-00000033954-i04.jpg
case_images: FIG4
case_images: Microscopic examination showed a monomorphic population of spindle-shaped cells with scant cytoplasm, mild atypia, and conspicuous mitotic activity, with a fascicular growth pattern and areas of necrosis (Figures 3, 4).
case_images: Vimentin expression. Immunohistochemistry analysis of renal tissue (100x magnification): the neoplastic proliferation expresses Vimentin diffusely (blue arrow).
case_images: cureus-0015-00000033954-i05.jpg
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case_images: FIG5
case_images: Immunohistochemical evaluation was positive for Vimentin and epithelial membrane antigen (EMA) (Figures 5, 6).
case_images: EMA expression. Immunohistochemistry analysis of renal tissue (40x magnification): the neoplastic proliferation expresses EMA focally (blue arrow).. EMA: Epithelial membrane antigen
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case_images: PMC9867795_01_cureus-0015-00000033954-i06.jpg
case_images: FIG6
case_images: Immunohistochemical evaluation was positive for Vimentin and epithelial membrane antigen (EMA) (Figures 5, 6).