Primary mixed lymphoepithelioma-like carcinoma and intra-hepatic cholangiocarcinoma: a case report and review of literature.

Primary lymphoepithelioma-like carcinomas (LELC) of the hepatobiliary tract are quite rare and the majority are associated with the Epstein-Barr virus (EBV). Here we report an unusual case of intrahepatic cholangiocarcinoma (ICC), admixed with LELC in a 63 year-old Filipino woman who presented clinically with right flank and back pain. Histologically, the tumor showed a dense lymphocytic infiltrate, predominantly composed of CD3 (+) T cells, and two components: an undifferentiated carcinoma, morphologically similar to nasopharyngeal carcinoma, and a poorly differentiated ICC intimately admixed. Immunohistochemical studies revealed that both components were immunoreactive for AE1/AE3, cytokeratin 7 and, focally, for monoclonal CEA. Both components were negative for cytokeratin 20 and HePar 1. EBER-1 in situ hybridization was uniformly positive in the tumor cells. The presence of EBV in ICC and LELC suggests that the virus may be linked to the pathogenesis of both components of the tumor. The mechanism of virus-driven neoplastic transformation needs further study.