Trace Elements Homeostasis in Biological Samples as New Candidate Biomarkers for Early Diagnosis and Prognostic of Female Breast Cancer and Therapeutic Response: Systematic Review

Female breast cancer (BC) remains the most common cause of total cancer deaths around the world. Several studies have investigated BC biomarkers, but vital circulating biomarkers for early diagnosis of malignancy are still scarce. Thus, finding sensitive, selective and accurate biomarkers is required to get better BC outcome and to prolong patients’ survival. Therefore, this review investigated the feasibility of using circulating trace elements (TEs) as the new promising biological biomarkers for BC diagnosis and prevention.

We systematically searched EMBASE, Medline, Google Scholar, PubMed, SciELO, Scopus databases or Web of Science for original studies presenting the significant changes in the concentrations of circulating TEs in terms of serum, plasma or blood from female breast cancer patients.

The search yielded 2697 articles, of which 39 were considered for this review. The study showed that four essential TEs (Se, Cu, Zn and Mn) significantly decreased when only one essential trace element (Fe) increased consistently, while five toxics circulating TEs (Cd, Cr, Pb, Co, Mo) increased significantly with a significant difference compared to healthy groups. The essential TEs, Se and Cu were reported to decrease the most in fifteen and twenty-one studies, respectively. However, regarding the toxic circulating TEs, Cd and Pb were found to increase most significantly in seven studies. Among the essential TEs, Se and Zn were reported to have the most potential, with Cd and Pb having the most potential for use as new promising biomarkers to diagnose or prevent BC.

The findings provide an insight into the TEs circulating biomarkers for early BC diagnosis and prevention. Due to its high heterogeneity, meta-analysis was not assessed; hence, further investigation may be required on their clinical outcomes in BC with high sensitivity and specificity for accurate therapeutic response.