A rhabdoid cholangiocarcinoma is a very rare variant of sarcomatous cholangiocarcinomas. Here, we report a vimentin positive cholangiocarcinoma showing rhabdoid features in the entire tumor, with a very aggressive behavior. A 41-year-old woman was admitted to our hospital due to a huge hepatic mass. The resected liver revealed a 17x15cm sized solid mass with extensive necrosis and an infiltrative border. On microscopic examination, the entire tumor was composed of loosely cohesive round to polygonal cells, with rhabdoid features having abundant eosinophilic glassy cytoplasm and eccentrically located vesicular nuclei. Some tumor cells contained intracytoplasmic mucin vacuoles, but definite areas of glandular differentiation or spindle cell were not found. Immunohistochemical staining showed a diffuse strong positive reaction to pan-cytokeratin and vimentin, and focal positivity for the carcinoembryonic antigen. Other immunohistochemical stainings for cytokeratin 7, cytokeratin 20, S-100 protein, HMB-45, desmin, alpha-smooth muscle actin, c-kit, CD34, alpha-fetoprotein, anti-hepatocyte antigen, chromogranin and synaptophysin were all negative. After two months, the patient developed a local recurrence along the resection margin, and multiple hematogenous metastases to the lung and liver were seen on the follow-up CT scan.
Adult ; Cholangiocarcinoma/chemistry/*pathology ; Female ; Human ; Liver Neoplasms/chemistry/*pathology ; Magnetic Resonance Imaging ; Prognosis ; Rhabdoid Tumor/chemistry/*pathology ; Support, Non-U.S. Gov't ; Tomography, X-Ray Computed ; Vimentin/analysis

OBJECTIVETo study the clinicopathologic features and differential diagnosis of atypical teratoid/rhabdoid tumor (AT/RT) occurring in the central nervous system.

METHODSTwo cases of AT/RT were studied by hematoxylin-eosin, reticulin and immunohistochemical staining. The clinical and pathologic features were analyzed and the literatures reviewed.

RESULTSHistologically, AT/RT was characterized by the presence of rhabdoid cells associated with various degrees of primitive neuroectodermal, epithelial or mesenchymal differentiation. Abundant reticulin fibers and a complex immunophenotype were observed. The tumor cells were positive for vimentin, CD99, epithelial membrane antigen, cytokeratin, glial fibrillary acidic protein, S-100 protein, neurofilament, desmin and smooth muscle actin. They were negative for synaptophysin, MyoD1, placental alkaline phosphatase and HMB45.

CONCLUSIONSAT/RT is a highly malignant tumor occurring in the central nervous system. It manifests mainly in children and occasionally in adults. The tumor is characterized by a heterogeneous histologic and immunohistochemical phenotype. It needs to be distinguished from a number of central nervous system tumors, including medulloblastoma, primitive neuroectodermal tumor, germ cell neoplasm and rhabdoid meningioma.

12E7 Antigen ; Actins ; analysis ; Adult ; Antigens, CD ; analysis ; Brain Neoplasms ; metabolism ; pathology ; Cell Adhesion Molecules ; analysis ; Child, Preschool ; Desmin ; analysis ; Glial Fibrillary Acidic Protein ; analysis ; Humans ; Immunohistochemistry ; Keratins ; analysis ; Male ; Mucin-1 ; analysis ; Muscle, Smooth ; chemistry ; Neurofilament Proteins ; analysis ; Rhabdoid Tumor ; metabolism ; pathology ; S100 Proteins ; analysis ; Teratoma ; metabolism ; pathology ; Vimentin ; analysis