The Association between Selenium and Epithelial Ovarian Cancer among Women: A methodology and comments from the Systematic Review and Meta-analysis

Abstract Background Ovarian cancer is the sixth most prevalent and fatal cancer among females worldwide. Antioxidants have some proven anticancer effects by limiting oxidative stress. Selenium is a powerful antioxidant and protects cells from the destruction caused by peroxides. This study aimed to determine the association between selenium intake and Epithelial Ovarian Cancer among women, who had not undergone an oophorectomy. Methods and analysis A comprehensive electronic search was carried out according to the prepared search strategy from the starting date of the PubMed/Medline, EMBASE, Scopus, Proquest, and Web of Science databases up to the 30th of September 2022 without limitations related to language or publication status. All observational studies, cross-sectional analytical studies, ecological studies, randomized control studies, and nonrandomized clinical trials were included in the systematic review. Studies will be screened by COVIDENCE. The exposure of interest was high selenium intake from either food sources, supplements, or high selenium supplements in blood and toenails. The data were extracted. The New Castle Ottawa Scale and the ROBINS-1 tool will be used to assess the bias of the selected studies. A narrative synthesis and meta-analysis will be conducted. The results are displayed via forest plots. All analyses will be performed using STATA-17. Commentary Ovarian cancer is the most fatal gynecological malignancy among women. Due to the lack of recommended screening tools, the identification of modifiable effective risk factors and preventive tools is essential for reducing the ovarian cancer burden. Selenium is a powerful antioxidant and prevents cell damage. Several studies have shown that selenium protects against the development of some selected cancers. Therefore it is envisaged that there is an inverse relationship between selenium and ovarian cancer for more expanded research study for the future ovarian cancer preventive strategies. Systematic review registration: Registered in the International Prospective Register of Systematic Reviews (PROSPERO)- CRD42022356472