ASSOCIATION OF EPSTEIN-BARR-VIRUS WITH GASTRIC-CARCINOMA WITH LYMPHOID STROMA

Epstein-Barr virus (EBV) has been detected in lymphoepithelioma of nas opharynx and lymphoepitheliomalike carcinomas in various organs. To cl arify the association of EBV with gastric carcinoma with lymphoid stro ma, which often resembles lymphoepithelioma, the authors examined 22 s uch cases by polymerase chain reaction and in situ hybridization techn iques. In 18 informative cases, EBV DNA was detected by polymerase cha in reaction in 14 (77.8%) cases. including lymph node metastases. EBV RNA was detected within the nuclei of carcinoma cells by in situ hybri dization in all cases that were positive by polymerase chain reaction. Infiltrating lymphocytes and normal epithelia adjacent to carcinoma w ere EBV-negative. Southern blot analysis indicated clonal proliferatio n of tumor cells and episomal form of EBV. These findings suggest that EBV infection occurs before transformation and may be related to onco genesis of EBV-associated gastric carcinoma.