Abstract
BACKGROUND: Serum trace elements have for some time been suggested to influence the development of gastric cancer, but evidence is still lacking. METHODS: All newly diagnosed patients with gastric cancer were compared with healthy controls 1:1 matched by sex, age (±3 years), and place of residence during 2013-2015. The serum concentration of all trace elements was analyzed using inductively coupled plasma mass spectrometry. Heliobacter pylori infections in cases were diagnosed using the rapid urease test, while in controls were detected using the colloidal gold method. RESULTS: A total of 122 cases of gastric cardia cancer (GCC) and 177 gastric noncardia cancer (NCGC), and 299 matched healthy controls were included. Positive associations were found between serum copper and copper/zinc ratio and risk of overall gastric cancer (OR(4th vs 1st quartile): 2.42, 95% CI: 1.10-5.32 for copper; OR(4th vs 1st quartile): 11.7, 95% CI: 3.83-35.6 for copper/zinc ratio), and for both GCC and NCGC subtypes. Serum selenium was inversely associated with the risk of NCGC (OR(4th vs 1st quartile): 0.18, 95% CI: 0.07-0.51), while molybdenum seems to reduce the risk of GCC (OR(4th vs 1st quartile): 0.12, 95% CI: 0.03-0.47). Strong inverse associations were also detected between serum calcium and risk of all groups of gastric cancer (all p for trend<0.05). CONCLUSION: The current study indicated statistically significant positive associations between serum copper, copper/zinc ratio, and gastric cancer, as well as inverse associations among selenium, molybdenum, and calcium. The results shall be carefully interpreted before further in vivo animal studies show definitive evidence.