Epstein-Barr virus-associated gastric carcinoma in Mexico: Analysis of 135consecutive gastrectomies in two hospitals

Epstein-Barr virus (EBV) has been implicated in the genesis of gastric carc inoma. The presence of clonal episomal viral forms in the nuclei of neoplas tic gastric epithelial cells suggests that viral infection occurs before th e development of gastric carcinoma. Mexico is a country at high risk for ga stric cancer-it is the second cause of death among patients who die of canc er in that country. A series of 135 consecutive non-selected gastrectomies from two hospitals in Mexico City were analyzed to search for EBV in gastri c carcinomas. EBV-encoded small nonpolyadenylated RNA (EBER) in situ hybrid ization was performed on 5-mu m paraffin-embedded tissue sections. Age, gen der, anatomical site, histological type, and invasiveness of gastric carcin omas were obtained from the records in the corresponding Departments of Pat hology. Eleven (8.15%) of the 135 cases were EBER-1-positive gastric carcin omas. Six occurred in males and five in females. In three women, the neopla sia was localized in the antrum. Five of the 11 cases were lymphoepitheliom a-like carcinomas and, in two of them, an unusual foreign body-type inflamm ation was observed. Environmental factors could influence the distinctive p athologic features of EBV-associated gastric carcinoma in the Mexican popul ation.