en Oncology Oncology Review Article Review Article <span style="font-size:14px;"><span style="font-family:times new roman;"><span style="color:#0000FF;"><strong><em>Background</em></strong><em>:</em></span> Some studies have investigated the effects of iron on breast carcinogenesis and reported different findings about the association between Fe and breast cancer risk. This study was conducted to estimate this effect using meta-analysis method.<br> <span style="color:#0000FF;"><strong><em>Methods</em></strong><em>:</em></span> A total of 20 articles published between 1984 and 2017 worldwide were selected through searching PubMed, Scopus, Embase, Web of Science, and Cochrane Library. Keywords such Breast Cancer, Neoplasm, Trace elements, Iron, Breast tissue concentration, Plasma concentration, Scalp hair concentration, toenail concentration and their combination were used in the search.<br> <span style="color:#0000FF;"><strong><em>Results</em></strong><em>:</em> </span>The total number of participants was 4,110 individuals comprising 1,624 patients with breast cancer and 2,486 healthy subjects. Fe concentration was measured in the various subgroups in both case and control groups. There were significant correlations between Fe concentration and breast cancer in breast tissue subgroup (SMD: 0.67 [95% CI: 0.17 to 1.17; P=0.009]). Whereas, there was no meaningful difference in Fe status between women with and without breast cancer related to scalp hair and plasma subgroups; (SMD: -3.74 [95% CI: -7.58 to 0.10; P=0.056] and (SMD:-1.14[95% CI: -2.30 to 0.03; P=0.055], respectively.<br> <span style="color:#0000FF;"><strong><em>Conclusion</em></strong><em>:</em> </span>The present meta-analysis indicated a positive and straight association between iron concentrations and risk of breast cancer but because of high heterogeneity we recommend more accurate future studies</span></span> Breast Cancer, trace elements, Iron, Meta-analysis. 1 11 http://caspjim.com/browse.php?a_code=A-10-1275-1&slc_lang=en&sid=1 Akram Sanagoo sanagoo@goums.ac.ir 100319475328460019877 100319475328460019877 No Nursing Research Center, Golestan University of Medical Sciences, Gorgan, Iran Faezeh Kiani fkiani43@yahoo.com 100319475328460019878 100319475328460019878 No Student Research Committee, Ilam University of Medical Sciences, Ilam, Iran Marzieh Saei Gharenaz saeigarenaz@gmail.com 100319475328460019879 100319475328460019879 No Students Research Committee, Shahid Beheshti University of Medical Sciences, Tehran, Iran Fatemeh Sayehmiri fsayehmiri@yahoo.com 100319475328460019880 100319475328460019880 No Student Research Committee, Proteomics Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran Fatemeh koohi fkoohi92@gmail.com 100319475328460019881 100319475328460019881 No Social Determinants of Health Research Center, Birjand University of Medical Sciences, Birjand, Iran Leila Jouybari jouybari@goums.ac.ir 100319475328460019882 100319475328460019882 Yes Nursing Research Center, Golestan University of Medical Sciences, Gorgan, Iran Majid Dousti m.dousti65@yahoo.com 100319475328460019883 100319475328460019883 No Faculty of Medicine, Ilam University of Medical Sciences, Ilam, Iran