Renal epithelioid angiomyolipoma with epithelial cysts: demonstration of Melan A and HMB45 positivity in the cystic epithelial lining.

Renal angiomyolipoma (AML) may present as rare variants such as epithelioid and AML with epithelial cysts posing difficulties for the diagnosis to the surgical pathologist. We report a case of a 46-year-old male patient presenting a 5-cm solid tumor in the lower pole of the left kidney, with cystic changes at cut surface. The tumor exhibited 95% of epithelioid cells with atypical nuclei.