(a) Showing solid variant of clear cell adenocarcinoma of the bladder with clear cells rich in glycogen (hematoxylin-eosin original magnification ×200); (b) showing clear cell adenocarcinoma of the bladder with prominent tubulocystic pattern (hematoxylin-eosin magnification ×200); (c) immunohistochemical staining of clear cell adenocarcinoma cells for cytokeratin 7 (original magnification ×200) (A), epithelial membrane antigen (original magnification ×200) (B), and high MIB-1 activity (original magnification ×200) (C). Immunohistochemical stains for pan-cytokeratin and cytokeratin 20 were also positive (figures not shown); (d) showing nephrogenic adenoma small tubules and cysts lined by clear cells (hematoxylin-eosin, original magnification ×200); (e) showing clear cell adenocarcinoma of the ovary (for comparison) tubules and cysts lined by glycogen-rich clear cells (hematoxylin-eosin, original magnification ×200); (f) showing clear renal cell carcinoma confluent nests composed of cells with uniform clear cytoplasm (hematoxylin-eosin, original magnification ×200). Reproduced from Adeniran and Tamboli. [10]: with permission of American College of Pathologists.