Clinical relevance of tissue copper, selenium, and cadmium alterations in colorectal cancer

Imbalances in essential elements and altered levels of toxic elements are thought to play a role in colorectal cancer (CRC) development. This study assessed the concentrations of selected elements in CRC tissues and explored their associations with clinical parameters. Paired samples of tumor tissue and adjacent noncancerous tissue were collected from 62 patients with confirmed CRC. After microwave-assisted acid digestion, ten elements (Al, Cr, Mn, Fe, Ni, Cu, Zn, Se, Sr, Cd) were quantified using ICP-MS. Statistical analyses and machine-learning methods were applied to identify features discriminating clinical and demographic subgroups. Significant differences between tumor and healthy tissues were observed for Mn, Cu, Zn, Se, Sr, and Cd, with further variation linked to Tumor Node Metastasis (TNM) classification, clinical stage, and place of residence. Cadmium levels were higher in the healthy tissues of women (p_adj = 0.021), while selenium concentrations showed a decreasing trend with advancing disease (Stage I vs. III; p = 0.017, p_adj = 0.051). Boruta analysis identified lymph node status, TNM stage, and elevated tumor copper levels as key features associated with CRC. Elemental profiles in CRC tissues differ markedly from those in adjacent healthy tissues and exhibit meaningful associations with disease stage and sex. The distinctive copper pattern observed in tumor samples, together with clinical parameters, suggests that elemental profiling may complement standard diagnostic approaches and contribute to a deeper understanding of CRC biology.