case_images: PMC9167443_01
case_images: abdominal computed tomography (CT) scan demonstrates a mass in the right renal pelvis (arrow)
case_images: PAMJ-41-233-g001.jpg
case_images: PMC9167443_01_PAMJ-41-233-g001.jpg
case_images: F1
case_images: Chest and abdominal computed tomography (CT) scans were done, showing a 5x4cm enhanced irregular soft tissue mass in the mid-pole extended to the lower pole of the right kidney without evidence of metastases (Figure 1).
case_images: sections of renal mass show infiltrative epithelial nests in renal parenchyma: A) with foci of sarcomatoid feature; B) immunohistochemistry shows a positive reaction for pan-cytokeratin; C) GATA3; D) X200
case_images: PAMJ-41-233-g002.jpg
case_images: PMC9167443_01_PAMJ-41-233-g002.jpg
case_images: F2
case_images: An immuno histochemistry (IHC) study was done, revealing a positive reaction for pan-cytokeratin and GATA 3 on both epithelial and sarcomatoid components and a negative reaction for CK5/6, P63, PAX8, and CD10 confirming the diagnosis of the sarcomatoid variant of UC (Figure 2).
case_images: brain magnetic resonance imaging (MRI) shows brain metastasis (arrow)
case_images: PAMJ-41-233-g003.jpg
case_images: PMC9167443_01_PAMJ-41-233-g003.jpg
case_images: F3
case_images: After two months, she developed severe headaches, and magnetic resonance imaging (MRI) showed brain metastasis (in the left temporal lobe, 9mm peripheral ring-enhancing lesion with crescent increased attenuation and adjacent edema) (Figure 3).