Abstract
RATIONALE: Lymphoepithelioma-like carcinoma (LELC) is a rare malignant tumor that can occur in many areas of the body. The pathogenesis of LELC remains unknown, but Epstein-Barr virus (EBV) has been shown to be strongly correlated with LELC at several anatomic sites, including the lungs and thymus. To the best of our knowledge, EBV-associated LELC has never been reported in both the posterior mediastinum and liver. Herein, we report the case of a 41-year-old female diagnosed with LELC in both the posterior mediastinum and liver and discuss whether it is beneficial to perform surgery on advanced LELC when resectable metastases are found. PATIENT CONCERNS: The patient was a 41-year-old woman who had been suffering from intermittent pain in the upper right quadrant for 3 months without obvious cause and was admitted to our hospital with occasional nausea without vomiting. DIAGNOSIS: Her cancer antigen 125 and cytokeratin 19 fragment levels were elevated, whereas alpha-fetoprotein and alanine aminotransferase were normal. Computed tomography (CT) and magnetic resonance imaging revealed a mass in the S6 segment of the liver. Whole-body positron emission tomography/computed tomography (PET/CT) revealed a 3.2-cm mass in the posterior mediastinum and a 6.7-cm mass on the right side of the liver. We made a diagnosis of LELC based on the histological and immunohistochemical findings of specimens obtained by operation. However, it was difficult to determine the primary origin of the tumor. INTERVENTIONS: The patient underwent mediastinal tumor resection, hepatectomy, and diaphragmatic repair. Thereafter, she was administered paclitaxel and cisplatin as adjuvant chemotherapy. OUTCOMES: The postoperative course was uneventful, and the patient was discharged 10 days later. Although she was administered paclitaxel and cisplatin as adjuvant chemotherapy, we noted recurrence during the 4-month follow-up examination. Then, the patient passed away 5 months after surgery. LESSONS: We present the first case of LELC found in both the posterior mediastinum and liver and describe the functionality of PET/CT for finding occult carcinomas and identifying their primary tumor origin. Additional studies are urgently needed to discover whether it is beneficial to perform surgery on advanced LELC when resectable metastases are revealed by PET/CT.