Mixed Epithelial and Stromal Tumor of the Kidney with Extension into Inferior Vena Cava: Case Report and Discussion of Adult Biphasic Cystic Renal Lesions and the Significance of Vascular Involvement

Figure 3

Cystic and biphasic tumor with benign, spindle cell stroma, focally resembling ovarian stroma, arranged with increased density in pericystic areas. Epithelial lining of cystic spaces is composed of a monolayer with cuboidal, flattened, and, focally, a hobnail appearance. No morphologic features of dysplasia are identified. Hematoxylin and eosin original magnification: 300x.