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

Publication year: 2011
Source: Annals of Diagnostic Pathology, In Press, Corrected Proof, Available online 14 June 2011

José do Egypto Pereira, Filho , Daniele, Meneses de Amorim , Gloria Maria Maranhão, Sweet , Luiz Antonio, Rodrigues de Freitas , Paulo Roberto Fontes, Athanazio , …

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. A small focus of typical AML was observed. The immunoprofile of tumor cells was classical of AML including expression of melanocytic markers such as HMB45 and Melan A. We report the immunohistochemical study of the cystic component…