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Image Description

Gross Pathology: Clear cell sarcoma of kidney (CCSK) presents as a single, firm, large mass (measuring up to 25 cm; mean size 11.3 cm) centered in the renal medulla. The tumor is circumscribed and sharply demarcated from the adjacent kidney which is often markedly distorted.

The cut surface has a homogenous pale, pink tan to white, soft mucoid appearance. Cyst formation and hemorrhage are common. Cystic change may be so dominant in some cases that imaging studies and gross appearance give an impression of cystic nephroma (multilocular cyst). Although grossly circumscribed, it frequently infiltrates into the adjacent renal parenchyma, entrapping isolated renal tubules and glomeruli. Gross renal vein invasion is seen in about 5% of cases.

Image courtesy of Dr. Jean-Christophe Fournet, Paris, France; humpath.com; Used with permission.

Image 52 of 85