BRCA1 and breast cancer: As a comparator group for the gBRCA1 cohort, we utilized patients diagnosed with stage I-III TNBC with recurrent breast cancer who had tested negative for variants in BRCA1 and BRCA2. In a competitive risk analysis using death as a competing risk factor, the cumulative incidence of brain metastasis did not differ between gBRCA1 patients and TNBC noncarrier patients.