BRCA1 and breast cancer: BRCA-mutated patients, compared to other patients, developed BC at a younger age, especially second BC (P=0.041), and had a higher family history of BC/OC, especially for I-degree relatives of OC patients (P=0.039), which are both predictable results given the higher penetrance of mutations in BRCA1/2 genes (Tables 1 and 2).