Composite tumor of metanephric adenoma and Wilms’ tumor of the kidney: A case report and review of the literature

Metanephric adenoma (MA) and Wilms' tumor (WT) are two distinct types of renal tumors. Composite MA and WT of the kidney are extremely rare. Here, a rare case of composite MA and WT of the kidney in a 36-year-old male is described. MA and WT each have their own histopathological features, respectively, and they focally share morphological similarities, which can be a diagnostic challenge. Immunohistochemistry is useful in the differential diagnosis of MA and WT. The histopathological features and differential diagnosis of the composite tumor are emphasized here to promote a better and broader understanding of this less understood subject.