ESR1 and breast cancer: The prevalence of bilateral BC, a personal history of BC, a personal history of other BRCA-related cancers (ovarian cancer and pancreatic cancer), a family history of BC, and a family history of other BRCA-related cancers (ovarian cancer, pancreatic cancer, and prostate cancer); estrogen receptor (ER) status; and Ki67 and human epidermal growth factor receptor 2 (HER-2) status were significantly different between the gBRCA mutation group and the non-gBRCA mutation group (all p < 0.050).