Presence of Trace Metals in the Biological Samples of Prostate Cancer Patients: A Systematic Review of Case-Control Studies

<b>Background/Objective:</b> Prostate cancer (PCa) is the leading cause of death in the ageing male population across the globe, and trace metals have garnered much attention due to their sometimes-dual role in cellular mechanisms, as such contribute to the development and progression of prostate cancer. <b>Methods:</b> This review consolidates the results of case-control studies that investigated the concentrations of certain trace metals-Arsenic (As), cadmium (Cd), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), selenium (Se), and zinc (Zn) in various biological samples. <b>Results:</b> There are decreased concentrations of Se and Zn and increased Cd concentrations in samples of PCa patients when compared to healthy controls. As, Hg, Ni, and Pb concentrations have proven to be insignificant. <b>Conclusions:</b> There are other variables to consider and limitations that need to be investigated in studies of this nature; however, the results have been consistent in that increased exposure to toxic metals such as Cd, along with a deficiency in protective essential nutrients like Zn and Se, tends to produce a prostatic environment.