Metanephric Adenoma : Gross Pathology

Comments:
Gross Pathology: Metanephric adenomas (MA) are generally unilateral, solitary, well-circumscribed and unencapsulated tumors that are sharply demarcated from the adjacent normal kidney. Rare cases have discontinuous or continuous capsule.

The cut surface is solid, homogenous and light tan, yellow, or gray in color. The tumor size ranges from 0.5 to >15 cm, with a mean diameter of 5 to 6 cm. Foci of hemorrhage, necrosis, or cystic degeneration may be present. Some tumors show areas of calcification and may even be entirely calcified in rare instances.