Selenium, Zinc, and Plasma Total Antioxidant Status and the Risk of Colorectal Adenoma and Cancer

Selenium (Se), zinc (Zn), and copper (Cu) are known to be involved in carcinogenesis and participate in the defence against reactive oxygen species (ROS). This study aimed to evaluate the clinical utility of serum Se, Zn, and Cu concentrations and plasma total antioxidant status (TAS) in the diagnosis of colorectal cancer (CRC) and colorectal adenoma (CRA) in a population of low Se and borderline Zn status. Based on clinical examination and colonoscopy/histopathology, the patients (n = 79) were divided into three groups: colorectal cancer (n = 30), colorectal adenoma (n = 19), and controls (CONTROL, n = 30). The serum Se concentration was lower in the CRC group than in the CRA group (by 9.1%, p < 0.0001) and the CONTROL group (by 7.9%, p < 0.0001). In turn, the serum Zn concentration was decreased in the CRA group (by 17.9%, p = 0.019) when compared to the CONTROL group. Plasma TAS was lower in the CRC group (by 27.8%, p = 0.017) than in the CONTROL group. In turn, the serum Zn concentration was decreased in the CRA group when compared to the CONTROL group. Plasma TAS was lower in the CRC group than in the CONTROL group. ROC (receiver operating characteristic) curve analysis revealed that the Se level was of the highest diagnostic utility for the discrimination of the CRC group from both the CRA group (area under ROC curve (AUC) 0.958, sensitivity 84.21%, specificity 100%) and the CONTROL group (AUC 0.873, sensitivity 100%, specificity 66.67%). The Zn and TAS levels were significantly accurate in the differentiation between the groups. An individualised risk of colorectal adenoma and cancer approach could comprise Se, Zn, and TAS assays in the population.