ESR1 and breast neoplasm: Independent samples t-test in 53 breast tumors indicated that decreased expression of BRCA1 significantly related to young age at diagnosis (< 50 years, p = 0.028), lymph node involvement (p = 0.04), and grade III (p = 0.04) in breast tumor samples, but it did not significantly associate with tumor size and ER/PR/HER2 status of the studied population.