case_images: PMC3649601_01
case_images: Gross Pathological Findings: Cut surface of the kidney shows that the tumour was firm grey white, 7.5 x 5.5 x 4.5 cm in size, replacing most of the kidney
case_images: IJU-29-53-g001.jpg
case_images: PMC3649601_01_IJU-29-53-g001.jpg
case_images: F1
case_images: The neoplasm appeared to abut the pelvis but there was no infiltration into pelvic or perirenal fat [Figure 1].
case_images: Microphotograph of neoplasm showing slightly nodular architecture due to varying cellularity and was composed of spindle cells with thin tapered bland nuclei an indistinct cytoplasm (hematoxylin and eosin stain, x100)
case_images: IJU-29-53-g002.jpg
case_images: PMC3649601_01_IJU-29-53-g002.jpg
case_images: F2
case_images: Microscopically the tumour had a slightly nodular architecture due to varying cellularity and was composed of spindle cells with thin tapered bland nuclei an indistinct cytoplasm [Figure 2].
case_images: Microphotograph of neoplasm showing concentric arrangement around entrapped tubules, imparting 'onion skin appearance' (hematoxylin and eosin stain, x200)
case_images: IJU-29-53-g003.jpg
case_images: PMC3649601_01_IJU-29-53-g003.jpg
case_images: F3
case_images: Focally, a concentric arrangement around entrapped tubules and vessels, imparting 'the onion skin' morphology, was noted [Figure 3].
case_images: Microphotograph of neoplasm showing well demarcation from the adjacent kidney but without a definite capsule (hematoxylin and eosin stain, x200)
case_images: IJU-29-53-g004.jpg
case_images: PMC3649601_01_IJU-29-53-g004.jpg
case_images: F4
case_images: The tumour was well demarcated from the adjacent kidney, but without a definite capsule [Figure 4].
case_images: Microphotograph of neoplasm showing blood vessels having hypercellularity around endothelium with thickened walls but there were no features of dysplasia (H and E stain, x200)
case_images: IJU-29-53-g005.jpg
case_images: PMC3649601_01_IJU-29-53-g005.jpg
case_images: F5
case_images: Some blood vessels showed hypercellularity around the endothelium with thickened walls but there were no features of dysplasia [Figure 5].
case_images: Immunohistochemical staining for CD 34 showing focal positivity (x200)
case_images: IJU-29-53-g006.jpg
case_images: PMC3649601_01_IJU-29-53-g006.jpg
case_images: F6
case_images: On immunohistochemistry, the cells were positive for Vimentin, focally positive for CD-34 [Figure 6] and negative for WT-1, Desmin and Smooth muscle actin.