The frequency of sister chromatid exchange (SCE) in patients with gastric cancer is significantly higher than that in normal individuals; however, their characteristics have not been studied. In present study, we analyzed the correlation between the cytogenetic instability of gastric cancer patients’ peripheral lymphocytes with or without hypoxia and the characteristics of gastric cancer patients. The primary lymphocyte cultures obtained from blood samples of 40 healthy donors and 69 patients with gastric c…