Fine needle aspiration biopsy of epithelioid angiomyolipoma. A case report.
BACKGROUND
Epithelioid angiomyolipoma (AMYL) is a variant of angiomyolipoma characterized by sheets of epithelioid cells that may mimic renal cell carcinoma. This is the first report describing the fine needle aspiration biopsy features of this lesion.


METHODS
A 47-year-old man with a history of epithelioid angiomyolipoma of the kidney treated with nephrectomy nine months previously presented with a recurrent retroperitoneal mass and multiple nodular liver lesions. Fine needle aspiration biopsy of one of the liver lesions showed fragments and sheets of noncohesive epithelioid cells with thin cytoplasm, markedly atypical nuclei, and scattered bizarre and multinucleated forms. The epithelioid cells focally expressed HMB-45 and were nonimmunoreactive, with epithelial markers.


CONCLUSIONS
Epithelioid AMYL may pose differential diagnostic problems with high grade carcinoma, especially renal cell, hepatocellular and metastatic carcinoma. An awareness of this entity and its characteristic cytologic features and immunoreactivity with HMB-45 is helpful in its identification.
Division of Anatomical Pathology, Department of Laboratory Medicine, Ottawa Hospital, Civic Campus, 1053 Carling Avenue, Ottawa, Ontario, Canada K1Y 4E9.
K T
KT
Mai
H M
HM
Yazdi
D G
DG
Perkins
A
A
Thijssen
D018207:Angiomyolipoma / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology*; D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor / Q000378:metabolism; D001707:Biopsy, Needle; D002292:Carcinoma, Renal Cell / Q000175:diagnosis; D003937:Diagnosis, Differential; D006801:Humans; D007680:Kidney Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology*; D008113:Liver Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D008297:Male; D058950:Melanoma-Specific Antigens; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism; D016609:Neoplasms, Second Primary / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology
D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D058950:Melanoma-Specific Antigens; D009363:Neoplasm Proteins