(A) Sharply demarcated gray-tan nodular tumor occupying the upper and middle poles with focally hemorrhagic areas on cut surface (Gross). (B) Biphasic renal tumor composed mainly of medium to large epithelioid cells and focal areas of spindle cells around numerous small blood vessels (H&E, Original magnification ×100). (C) Perivascular epithelioid cells arranged in solid nests or cords with well-defined cytoplasmic borders and abundant cytoplasm that varied from eosinophilic and granular to clear (H&E, Original magnification ×400). (D) Moderate-to-severe nuclei pleomorphism and hyperchromatism with bizarre multinucleated giant cells and mitoses (H&E, Original magnification ×400).
Armah and Parwani Diagnostic Pathology 2007 2:45 doi:10.1186/1746-1596-2-45