Metanephric Adenoma : Differential

Comments:
Differential Diagnosis: The main differential diagnosis of metanephric adenoma (MA) is epithelial-predominant Wilms tumor (WT) in pediatric patients and solid variant of papillary renal cell carcinoma (sPRCC) in adults. An immunohistochemical panel consisting of WT1, CD57, CK7, and AMACR, in conjunction with H&E-stained slides, can resolve most of the cases.

Epithelial-predominant WT usually has a pseudocapsule. There is greater degree of nuclear pleomorphism, prominent nucleoli and brisk mitotic activity. Other components, including blastema and stromal elements may be present. CD57 is usually negative. Most cases of epithelial-predominant WT lack BRAF mutations.