Article
Renal epithelioid angiomyolipoma with epithelial cysts: demonstration of melan A and HMB45 positivity in the cystic epithelial lining
Registro en:
PEREIRA FILHO, J. do E. et al. Renal epithelioid angiomyolipoma with epithelial cysts: demonstration of melan A and HMB45 positivity in the cystic epithelial lining. Annals of Diagnostic Pathology, v. 16, p. 397–401, 2012.
1092-9134
10.1016/j.anndiagpath.2011.03.004
Autor
Pereira Filho, José do Egypto
Amorim, Daniele Meneses de
Sweet, Glória Maria Maranhão
Freitas, Luiz Antonio Rodrigues de
Athanazio, Paulo Roberto Fontes
Athanazio, Daniel Abensur
Resumen
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 in an epithelioid AML. In contrast to the
immunoreactivity reported in typical AML, the present case shows obvious expression of
melanocytic markers in the cystic epithelial lining. This is strong evidence that these cysts are
neoplastic and derived from AML, rather than entrapped native collecting duct epithelium.
© 2012 Elsevier Inc. All rights reserved.