Wang B, Lu Z, Huang Y, et al. - Researchers systematically evaluated if there was any connection between hypothyroidism and breast cancer risk, via this meta-analysis, and if an increased risk of breast cancer is linked to thyroid hormone replacement therapy. Using the electronic database platform, they obtained relevant articles. Overall, 19 studies, including 6 cohort studies and 13 case-control studies, were analyzed. In the European population, the risk of breast cancer may be attenuated by hypothyroidism according to the findings; it was was also not significantly correlated with breast cancer risk in non-European populations. There was no significant correlation between thyroid hormone replacement therapy and breast cancer risk.