Fig. 2

Glandular differentiation of the undifferentiated carcinoma with rhabdoid features. (a) Tumor with neighbored biliary intraepithelial neoplasia of the gallbladder and liver. (H&E staining; bar: 2,5 mm). (b) High power aspect of the biliary intraepithelial neoplasia (H&E staining; bar: 250 μm). (c) Gland formation with atypical nuclei (H&E staining; black bar: 100 μm). (d) Immunohistochemistry for cytokeratin 8 with positive cytoplasmic staining in the tumor cells (top). For internal positive control see bile ducts (bottom) (bar: 500 μm). (e) Immunohistochemistry for PBRM1 without nuclear staining in the tumor cells (negative). Note nuclear staining in inflammatory cells. (f) Loss of nuclear SMARCA2 expression by immunohistochemistry in tumor cells. (g) Immunohistochemistry for SMARCA4 with retained expression. (e-g: 400 x magnification)