EPSTEIN-BARR VIRUS-POSITIVE MULTIPLE EARLY GASTRIC CANCERS AND DYSPLASTIC LESIONS - A CASE-REPORT

Epstein-Barr virus (EBV) has been implicated as a causal virus of gast ric cancer with episomal monoclonality, elevated antibodies and a uniq ue morphologic expression in the early intramucosal stage, but the inf ection mechanisms have not been demonstrated, EBV has been shown only in the cancerous lesions by the highly sensitive EBV-encoded small RNA in situ hybridization (EBER-ISH) method, not in the dysplastic mucosa adjacent to the cancer, A case is presented of multiple EBV-positive gastric cancer and dysplastic epithelium observed in a 52-year-old man . Serial cut sections of the gastrectomy specimen showed four small ca ncerous lesions, three of which were EBER-positive, and three EBER-pos itive, minute, non-cancerous dysplastic lesions, The three cancerous l esions were intramucosal cancer, with one having minimal submucosal in vasion forming a lymphoepithelioma-like histology, All of these EBER-p ositive cancerous and dysplastic lesions showed intense CD8 T-lymphocy tic infiltration. There was no such findings in the EBV-negative cance rous lesion, It was concluded that EBV infection may occur in the epit helial cells of atrophic gastric mucosa, and progress to cancer with m onoclonal expansion through the EBV-positive dysplastic change. Cytoto xic T-lymphocytic reactions can occur even in the dysplastic lesions. Multifocal EBV infection in the gastric mucosa may occur and, if neces sary, total gastrectomy is recommended in such a case.