Case report: Intrahepatic cholangiocarcinoma with lymphoepithelioma-like carcinoma component

We report an unusual case of intrahepatic cholangiocarcinoma (ICC) with lymphoepithelioma-like carcinoma (LELC) component in a 60-yr-old woman who was found incidentally to have an abdominal mass. Histologically, the tumor showed 2 distinct patterns with dense lymphoplasma cell infiltration. The first pattern, comprising approximately 20% of total tumor volume, showed the features of lymphoepithelioma-like carcinoma, as commonly found in nasopharyngeal carcinoma (NPC). The second pattern was a moderately differentiated cholangiocarcinoma. In situ hybridization for Epstein-Barr virus (EBV)-encoded RNA (EBER) showed positive nuclear labeling of tumor cells in both patterns, but not in surrounding inflammatory cells. By the polymerase chain reaction, the latent membrane protein gene (LMP-1) in this case was shown to have a 30 bp deletion in the C-terminus, a unique feature in high prevalence areas of undifferentiated nasopharyngeal carcinoma, such as in Taiwan. Presence of the EBV genomes and their expression in the cholangiocarcinoma cells suggested that EBV may play an important role in the pathogenesis of ICC with LELC. In this case, it is unclear why only 20% of the glands were transformed into LELC. The mechanism whereby EBV transforms the malignant glands into the distinct morphology resembling NPC warrants further investigation.