544. Non-Epstein-Barr Virus Associated Lymphoepithelioma-Like Carcinoma of the Esophagus With Surgical Treatment: A Report of Two Cases

Abstract

Lymphoepithelioma-like carcinoma (LELC) can occur in many organs such as lung, stomach, skin, breast, bile ducts, esophagus, and other many organs. Esopahageal lymphoepithelioma-like carcinoma is an extremely rare disease. LELC has been reported to be associated with Epstein-Barr virus (EBV) in some organs, although there are many controversies. Here, we report a surgically treated two cases of non-Epstein-Barr virus associated LELC of the esophagus. Case 1was a 46-year-old woman who was presented epigastralgia while eating. Upper gastrointestinal endoscopy showed a submucosal tumor in the lower esophagus. Biopsies were taken, and they identified atypical cells proliferating follicular manner and heavy infiltration of lymphocytes. Case 2 was a 71-year-old man who was pointed out to have a tumor in the esophagus by barium examination and was referred to our hospital. Upper gastrointestinal endoscopy showed submucosal tumor was found 23-26 cm from the cut tooth. Endoscopic Ultrasound-guided Fine Needle Aspiration (EUS-FNA) was performed and diagnosed with LELC. These patients underwent subtotal esophagectomy with lymphadenectomy and reconstruction with gastric tube. Case1 was pathologically diagnosed with LELC, SM3, INFa, ly0, V0, pIM0, pPM0 (100mm), pDM0 (120mm), pRM0, pN0, cM0, pStageI, and case2 was diagnosed with LELC, ly1, V1, pIM0, pPM0, pDM0, pRM0, pN0, cM0, pStageI, according to the 10th edition of Japanese classification of Esophageal cancer. Immunohistochemical staining of the specimen from case 1 was positive for AE1/AE3, P40, p63, and negative for CD56 and chromogranin A. Immunohistochemical staining of the specimen from case 2 was positive for CK, EMA, P40, and negative forαSMA and desmin. EBV was not detected by EBER in situ hybridization in the specimen from both patients. LELC is relatively common in salivary glands, thymus, lungs, stomach, skin, and cervix, and EBV that directly infects epithelial cells or infects lymphocytes infects epithelial cells and infects them. EBV infects epithelial cells and is thought to be associated with carcinogenesis of these organs. However, esophageal LELC is rare and it has been argued that EBV may not be involved. In these two cases, EBV was not detected in situ hybridization.