Fig. 3

Renal clear cell carcinoma metastasis to the breast. a A low-power view showed a metastatic clear cell RCC in the breast with atrophic breast parenchyma in the background. The apparent circumscription and the pseudocapsule surrounding the carcinoma were noted (black arrows), (hematoxylin-eosin, original magnification 40×). b A medium-power view showed infiltration of clear cells into the surrounding breast tissue (hematoxylin-eosin, original magnification 100×). c Clear cells with distinct cytoplasmic borders were arranged in nests separated by a thin fibrovascular stroma (hematoxylin-eosin, original magnification 200×). d A high-power view revealed foamy, vacuolar cytoplasm and large nucleoli consistent with clear cell RCC (hematoxylin-eosin, original magnification 400×). e Renal neoplastic cell showing strong membranous staining with CD10 (immunohistochemistry, original magnification 400×). f Diffuse and strong cell cytoplasm staining for vimentin was observed in clear cell RCC. Positive cells displayed brownish yellow granules on the surface, cytoplasm, and intercalated discs (immunohistochemistry, original magnification 400×)