Eosinophilic solid and cystic renal cell carcinoma with aggressive behavior: Two case reports

Figure 1 Images of hematoxylin and eosin staining and immunostaining in case 1. A: Low-power microscopic examination revealed eosinophilic solid and cystic renal cell carcinoma (ESC RCC) with cystic and solid architecture; B: The tumor cells had abundant granular eosinophilic cytoplasm with prominent fine or coarse basophilic granular cytoplasmic stippling; C: Eosinophilic cytoplasmic globules; D: The tumor cells lining the septa showed a hobnail arrangement; E: Focal intracytoplasmic vacuoles were observed; F: CK20 expression in ESC RCC cells.

Figure 2 Images of hematoxylin and eosin staining and immunostaining in case 2. A: Tumor cells were arranged in an acinar-like, microcyst, and pseudo-papillary pattern, and cells lining septa had a hobnail morphology; B: The cells exhibited a voluminous eosinophilic cytoplasm with various sizes of basophilic granular stippling; C: Immunohistochemical staining for CK20.