[Serum and tissue copper, zinc and selenium levels in patients with gastric carcinoma]

Serum and tissue copper, zinc and selenium levels were measured in patients with gastric carcinoma. The mean level of serum copper in patients with gastric carcinoma (42 cases) was 950 +/- 130 ug/L, which was higher than 800 +/- 70 ug/L of the control (30 cases, P less than 0.05). The serum selenium level in patients with gastric carcinoma was lower than that in the control (63 +/- 15 ug/L vs 85 +/- 8 ug/L, P less than 0.05). No significant difference in serum zinc level was found between the patient and control groups. In cancer tissues, the mean concentration of copper was 13.5 +/- 2.6 micrograms/g dry weight, which was much higher than 7.1 +/- 1.6 micrograms/g dry weight in the intact gastric mucosa (P less than 0.01). The activity of superoxide dismutase (SOD) in cancer tissue was 95 +/- 10 u/mg-protein, which was lower than 124 +/- 12 u/mg-protein in the intact gastric mucosa (P less than 0.05). The above changes may facilitate production of free radicals, tissue damage and carcinogenesis.