Epstein-Barr Virus–Associated Lymphoepithelioma-like Gastric Carcinoma

This article provides an overview of the pathology of Epstein-Barr virus (EBV)–associated lymphoepithelioma-like gastric carcinoma, highlighting its unique morphology and clinical features. Lymphoepithelioma-like gastric carcinoma is a rare neoplasm of the stomach with a better prognosis than conventional adenocarcinoma. Most lymphoepithelioma-like gastric carcinomas are associated with EBV infection, while a subset is associated with microsatellite instability. Even though there is a very strong association with EBV, its exact role in carcinogenesis still remains to be elucidated in those cancers that harbor EBV. Distinctive histology and demonstration of EBV using in situ hybridization, polymerase chain reaction, or Southern blotting and immunohistochemistry for the DNA mismatch repair genes or polymerase chain reaction analysis of microsatellite loci to assess microsatellite instability helps to make the diagnosis.