comparison of the Serum Levels of Trace Elements in Areas with High or Low Rate of Esophageal Cancer.

BACKGROUND There is a critical role for trace elements in cancer prevention. Since northeast Iran is known as a high risk area for esophageal cancer, this study was designed to compare the serum levels of some trace elements in high and low rate areas of Golestan province. METHODS We used 240 fasting serum samples obtained in 2011 from eastern and western parts of Golestan province during the non-communicable diseases' screening program. To carry out laboratory examinations, the samples were firstly deproteinated and then the concentrations of the intended elements were measured by an atomic absorption spectrometer. A total of 227 samples were used in the present study and the remaining 13 samples were excluded due to inappropriate conditions. RESULTS The mean serum level of zinc in the high-risk region was significantly lower than that in the low-risk region. But no significant difference was detected in serum levels of copper, magnesium, and manganese in the low-risk and high-risk regions. CONCLUSION As this study was an ecological study with no comparison between patients with cancer and healthy population, its results cannot be used for the general population. Therefore, complementary studies including case-control studies are suggested for further evaluation of the relationship between these elements and the incidence of esophageal cancer.