lymphoepithelioma - like carcinomas have a histomorphology identical to that of undifferentiated nasopharyngeal carcinomas and have been described in various organs . lymphoepithelioma - like carcinomas of the liver , however , have rarely been reported , and the majority of them are considered to be lymphoepithelioma - like cholangiocarcinoma . histologically , lymphoepithelioma - like cholangiocarcinomas are composed of two components : an adenocarcinoma and a lymphoepithelioma - like carcinoma . to the best of my knowledge , only 16 cases of lymphoepithelioma - like cholangiocarcinoma have been reported in the medical literature [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 ] , and 11 of these cases were related to epstein - barr virus ( ebv ) infection [ 1 , 2 , 3 , 5 , 6 , 7 , 9 ] . here , a case of lymphoepithelioma - like cholangiocarcinoma that was not associated with ebv infection is presented . a 79-year - old man underwent abdominal computed tomography ( ct ) because of hepatitis b virus ( hbv)-associated cirrhosis . the abdominal ct revealed a 3.7  2.5  2.5 cm hypervascular mass near the dome of the left lateral lobe of the liver . the serum hbv surface antigen was positive and the anti - hepatitis c virus ( hcv ) antibody was negative . the liver function tests were normal , and the serum tumor markers , including alpha - fetoprotein , carcinoembryonic antigen and ca 19 - 9 , were within the reference ranges . the patient had type 2 diabetes . left lateral segmentectomy for the liver mass was performed . macroscopically , the tumor measured 3.5  2.5  2.5 cm and was pale gray , well defined , non - encapsulated , rubbery and solid ( fig . histologically , the tumor was composed of two components : an adenocarcinoma that formed irregular small glands and a lymphoepithelioma - like carcinoma that exhibited sheets of undifferentiated epithelial cells with lymphoid stroma ( fig . lymphoplasmacytic infiltrates were more predominant in the lymphoepithelioma - like carcinoma than in the adenocarcinoma . the nuclei of the tumor cells were similar in both components , and they were ovoid or pleomorphic with an irregular nuclear membrane , vesicular chromatin and occasional macronucleoli . the background liver showed cirrhotic nodules surrounded by fibrous bands and a considerable portal infiltration of lymphocytes . immunohistochemically , the adenocarcinoma component was diffusely positive for ae1/ae3 , cytokeratin ( ck ) 7 , ck19 and epithelial membrane antigen ( ema ) , while the lymphoepithelioma - like carcinoma component was focally positive for ae1/ae3 , ema , ck7 and ck19 ( fig . both components were diffusely positive for p53 protein , but they were negative for polyclonal carcinoembryonic antigen , heppar1 , alpha - fetoprotein , ck20 , vimentin , c - kit and cd56 . based on the histological analysis of the resected liver mass , the patient was diagnosed with intrahepatic lymphoepithelioma - like cholangiocarcinoma . examination of a resected para - aortic lymph node revealed metastasis exclusively of the lymphoepithelioma - like carcinoma component . the postoperative f - fdg pet - ct demonstrated no evidence of extrahepatic tumors , including nasopharyngeal cancer . after the operation , a radiation therapy performed to ablate the enlarged lymph nodes in the porta hepatis and retropancreatic areas was successful . three years later , a follow - up abdominal ct revealed two well - defined heterogeneous low - attenuated nodular lesions that measured 5 cm and 2 cm in greatest dimension , respectively . a needle biopsy of the nodule was performed , and histologically , a well - differentiated hepatocellular carcinoma was diagnosed . he is currently alive , without recurrence of lymphoepithelioma - like cholangiocarcinoma 54 months after surgery . lymphoepithelioma - like carcinoma is composed of undifferentiated epithelial cells with an intense lymphocytic infiltrate . unlike carcinomas of other organ sites , the majority of lymphoepithelioma - like cholangiocarcinomas are composed of two different components  an adenocarcinoma and a lymphoepithelioma - like carcinoma . there is only 1 reported case of the pure form of lymphoepithelioma - like carcinoma without well - formed tubules . in the present case , the adenocarcinoma and lymphoepithelioma - like carcinoma components presented several identical characteristics ; for example , both had a considerable amount of lymphocyte infiltrate without any conspicuous desmoplastic stroma , the nuclei of the adenocarcinoma and the lymphoepithelioma - like carcinoma resembled each other , and both components revealed diffuse immunoreactivity for p53 protein . however , immunohistochemically , some differences between the two components could be observed , e.g. contrary to the adenocarcinoma , the lymphoepithelioma - like carcinoma showed only focal positivity for epithelial markers such as ae1/ae3 , ema , ck7 and ck19 . the histological and immunohistochemical findings in the present patient suggest that the adenocarcinoma component may have transformed to the lymphoepithelioma - like carcinoma . although the majority of reported lymphoepithelioma - like carcinomas of the liver were considered to be cholangiocarcinoma , to the best of my knowledge , 3 cases of lymphoepithelioma - like hepatocellular carcinoma have been reported [ 12 , 13 , 14 ] . in this patient , the presence of glandular structures showing diffuse positivity for bile duct markers , such as ck7 and ck19 , and negativity for hepatocyte markers , such as alpha - fetoprotein and heppar1 , was considered to be an indicator for the diagnosis of cholangiocarcinoma . most of these lymphoepithelioma - like cholangiocarcinoma cases except for 2 [ 1 , 3 ] were reported in the oriental countries , which are known as endemic areas of ebv infection . it has been suggested that ebv may play a role in the tumorigenesis of lymphoepithelioma - like cholangiocarcinoma . to the best of my knowledge , 7 of the 16 reported cases of lymphoepithelioma - like cholangiocarcinomas , including the present case , were negative for ebv [ 4 , 8 , 10 , 11 ] . one of the 7 ebv - negative patients had hcv cirrhosis   and 4 cases , including the present case , had hbv cirrhosis [ 6 , 10 ] . this finding suggests that hbv and hcv are also related with the pathogenesis of lymphoepithelioma - like cholangiocarcinoma . however , further collective studies are needed to confirm this hypothesis . according to the literature , the lymphocytes within lymphoepithelioma - like carcinomas are known to be predominantly t cells [ 6 , 8 ] . however , in the present case , the b and t cells infiltrated in nearly equal proportions and , interestingly , many plasma cells were mixed with them . szekely   reported that the prognosis of lymphoepithelioma - like cholangiocarcinoma seems to be better than that of ordinary cholangiocarcinoma . however , there is limited information regarding the prognosis and treatment of lymphoepithelioma - like cholangiocarcinomas because of the only limited number of reported cases . the present case was associated with metastasis to a para - aortic lymph node at the time of operation . postoperative radiation was given to the regional lymph nodes , and the patient is alive without recurrence of lymphoepithelioma - like cholangiocarcinoma 54 months after tumor removal , although a metachronous hepatocellular carcinoma developed recently .
lymphoepithelioma - like cholangiocarcinomas are rare tumors and most of them are related with epstein - barr virus ( ebv ) infection . here , a case of a patient with lymphoepithelioma - like cholangiocarcinoma not associated with ebv infection is presented . in a 79-year - old man with hepatitis b virus - associated cirrhosis , 
 a liver mass was detected on abdominal ct . 
 macroscopically , the resected tumor was pale gray , rubbery and well defined . 
 histologically , the tumor was composed of two components : an adenocarcinoma that formed irregular small glands and a lymphoepithelioma - like carcinoma that exhibited sheets of undifferentiated epithelial cells with lymphoid stroma . 
 lymphoplasmacytic infiltrates were more predominant in the lymphoepithelioma - like carcinoma than in the adenocarcinoma . 
 both components were roughly divided , but they gradually merged . 
 immunohistochemically , the adenocarcinoma component was diffusely positive for ae1/ae3 , cytokeratin 7 , cytokeratin 19 and epithelial membrane antigen , while the lymphoepithelioma - like carcinoma component was focally positive for them . however , both components were diffusely positive for p53 protein , and in situ hybridization using ebv - encoded rna 1 was negative in both components as well . 
 examination of a resected para - aortic lymph node revealed metastasis exclusively of the lymphoepithelioma - like carcinoma component .