Epstein-Barr virus (EBV) involvement in gastric cancer is demonstrated by uniform presence of viral RNA in carcinoma cells as detected by EBV-encoded small RNA in situ hybridization, monoclonal proliferation of EBV-infected carcinoma cells, and elevated antibodies. Our review of selected early gastric cancers found that 46 of 49 EBV-positive lesions (94%) but only four of 97 EBV-negative lesions (4%) conformed to a unique morphology, in which carcinoma cells formed lace patterns of branching and/or anastomosing structures with lymphocytic infiltration in and around the carcinoma nests in the mucosa. We conclude that EBV-related gastric carcinoma has a distinct and characteristic morphology in the early stage of development, and this lace pattern is a biomarker of EBV involvement in early gastric cancer.