Lipid-laden foamy macrophages in renal cell carcinoma. Potential frozen section diagnostic pitfall.
Lipid-laden foamy macrophages are characteristic of xanthogranulomatous pyelonephritis (XGP). We have encountered a case of renal cell carcinoma (RCC), with extensive necrosis, in which confluent sheets of foamy macrophages were a dominant feature. We describe the case and discuss the potential frozen section diagnostic problem in attempting to distinguish between confluent sheets of xanthoma cells a "reactive" change in RCC and xanthoma cells as a fundamental component of XGP. We propose that awareness of that problem should prompt the pathologist to request additional samples.
Iskandar
S S
SS
Department of Pathology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem.
Prahlow
J A
JA
White
W L
WL
D000368:Aged; D002292:Carcinoma, Renal Cell / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D005487:Foam Cells / Q000473:pathology*; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology*; D011705:Pyelonephritis, Xanthogranulomatous / Q000473:pathology*