Atypical metanephric adenoma - a case report and review of literature.

Metanephric adenoma (MA) is a rare renal neoplasm that generally occurs in adults and is considered to have a good prognosis. However, one case of MA with atypical histological features and distant metastasis and another case of metastasizing MA with typical cytologic features have been reported. The authors here report a case of MA with atypical histological features arising in the left kidney of an 18-year-old girl presenting with painless hematuria. Relevant literature is reviewed and discussed.