Heavy Metals in Biological Samples of Cancer Patients: A Systematic Literature Review

This systematic literature review investigates the role of heavy metals in cancer development and progression, focusing on breast, lung, prostate, and gastric cancers. It identifies heavy metals like arsenic, cadmium, chromium, lead, mercury, and nickel as carcinogens that increase tumor susceptibility and progression. The review highlights that cadmium is particularly linked to lung cancer and poor prognosis, and that heavy metals can alter DNA methylation, potentially reducing treatment sensitivity in breast cancer patients. Despite substantial evidence, the review notes significant gaps in the literature, especially regarding direct metal determination in cancer tissues, and calls for further research to better understand these impacts.