ABSTRACT
Objective To investigate the correlation between Epstein-Barrvirus (EBV) and H.pylori (Hp) infection and gastric cancer. Methods The EBV infection was examined by polymerase chain reaction (PCR) and in situ hybridiza-tion (ISH) in 100 samples of gastric cancer tissue and 82 samples of gastritis tissue. The Hp infection was detected by PCR. The correlation between EBV and Hp infection and clinical and pathological features was analyzed in patients with gastric cancer. Results The positive rates of EBV and Hp were significantly higher in gastric cancer tissues than those in gastritis tissues (9.0%vs 0 and 56.0%vs 40.2%, P＜0.05). There was significantly higher infection rate in EBV in cardia gastric can-cer than that of gastric cancer (16.3%vs 2.0%,P＜0.05). There were significantly higher infection rates in EBV and Hp in poorly differentiated carcinoma than those of well-differentiated carcinoma (15.7%vs 2.0%and 66.7%vs 44.9%, P＜0.05). There were no significant differences in EBV and Hp infection between gender, age, nationality and lymph node metastasis (P>0.05). There was no significant difference in Hp infection between different parts of gastric cancer. There was no correla-tion between EBV and Hp infection in gastric cancer tissues (r=0.137, P>0.05). Conclusion EBV and Hp infection are two independent factors in the development of gastric cancer, and both of them are associated with the malignant evolution of gastric cancer.