case_images: PMC6362796_01
case_images: Plain and contrast-enhanced computerized tomography showing the hilar Bosniak type 4 cyst with enhancing soft-tissue component (arrow)
case_images: UA-11-98-g001.jpg
case_images: PMC6362796_01_UA-11-98-g001.jpg
case_images: F1
case_images: The opposite kidney showed prompt uptake, excretion, and drainage of contrast [Figure 1].
case_images: Intraoperative picture showing the grayish tumor closely adherent to renal vessels
case_images: UA-11-98-g002.jpg
case_images: PMC6362796_01_UA-11-98-g002.jpg
case_images: F2
case_images: The cyst was dissected all around from the parenchyma, except the hilar region where it was firmly adherent to the main renal vein and artery [Figure 2].
case_images: Histopathological picture depicting the tumor composed of sheets of eosinophilic oncocytic cells (H and E, x10)
case_images: UA-11-98-g003.jpg
case_images: PMC6362796_01_UA-11-98-g003.jpg
case_images: F3
case_images: Histological examination of the tumor using hematoxylin and eosin stains showed nests of eosinophilic oncocytic cells (round or polygonal cells with moderate or abundant granular, eosinophilic cytoplasm, and small nuclei with granular chromatin) in a hypocellular stroma [Figure 3].
case_images: Tumor cells staining negatively for Hale's colloidal iron stain (x40)
case_images: UA-11-98-g004.jpg
case_images: PMC6362796_01_UA-11-98-g004.jpg
case_images: F4
case_images: The tumor cells did not take up Hale's colloidal iron stain [Figure 4].