Lymphoepithelioma-like carcinoma of the lung: a rare case report and review of the literature.

Lymphoepithelioma-like carcinoma (LELC), is a rare type of cancer and typically occurs in pharyngeal and foregut-derivative organs, Including the salivary glands, thymus, stomach and liver (1). Pulmonary LELC typically affects the young and non-smoking population, and is associated with Ebstein-Barr virus (EBV) infection (1,2). We present an rare case with a pulmonary mass on CT scan of the thorax, which was subsequently proved as a LELC of the lung and a brief review of the relevant literature. The patient is a 51-year old man, presented with shorthness of breath and cough for 1 months. Chest x-ray was normal (Figure 1). Chest CT scan showed a 30-25 mm heterogeneously enhanced mass lesion with well defined margin, In the left lower lobe of the lung (Figure 2). Bronchoscopy showed no endobronchial lesion. After the PET-CT, the patient was staged as cT2aN1M0 (Stage 2B) (Figure 3). He received video-assisted thoracoscopic surgery of left lower lobe of lung and mediastinal lymph nodes dissection (Figure 4,5). His Ebv-Dna is Positive in blood tests. The pathology, immunohistochemical staining,and in situ hybridization results confirmed LELC of lung (Figure 6). Using in situ hybridization with exhibition of abundant EBV-encoded small nuclear RNA, in the majority of tumor cells is done. He received 4 cycles of induction chemotherapy with cysplatine and vinoralbine. The patient was discharged from hospital with close follow-up. No recurrence has been detected so far. Primary pulmonary LELC is a rare malignant tumor which accounts for only 0.9% of all primary lung cancer (1,2). Previous studies have demonstrated that pulmonary LELC is strongly associated with EBV infection (1,2). The majority of pulmonary LELC patients receive complete resection, as well as chemotherapy and radiotherapy based on their clinical stage (1,2). Comparing to other non-small cell cancer (NSCLC), pulmonary LELC is more sensitive to chemotherapy and radiotherapy (1,2). LELC of lung may be mistaken histopathologically for metastatic nasopharyngeal carcinoma or lymphoma. Its association with latent EBV infection have major implications for diagnosis and treatment. We present this case, because, its an unusual case with a pulmonary mass of the thorax, which was proved as a LELC of the lung.