Fig. 3

Gross appearance and histopathologic examination of the tumor. a Appearance of the giant tumor on the left kidney during the surgery. A great amount of circuitous blood vessels are extensively distributed on the surface of the mass. b Postoperative gross pathologic examination of the specimen. The specimen measures 20.5 cm × 16 cm × 15 cm. Multiple tiny cysts of various sizes appear on the light brown or tan maximum cross-section of the giant solid tumor. c Pathologic examination of the lesion with hematoxylin–eosin staining (×200) reveals large cells with finely reticulated cytoplasm and small cells with abundant eosinophilic cytoplasm and perinuclear clearing