BRCA1 and breast cancer: What was noteworthy was that 10 articles3, 4, 6, 16, 27, 29, 30, 31, 32, 33 not only studied the prevalence of BRCA1 promoter methylation, but also elaborated clinicopathological characteristics in breast cancer patients with BRCA1 promoter methylation versus BRCA1-unmethylated tumors.