BRCA1 and breast cancer: Brekelmans et al. reported no difference in IBTR in 226 patients with a family history of BRCA1/2 compared with 311 patients with a family history of breast cancer but testing negative for BRCA1/2 in the family, and compared to 759 patients with sporadic breast cancer, with a mean duration of followup from 4.3 to 5.1 years [25].