BRCA1 and breast carcinoma: Secondary country-stratified analysis of 2,249 BRCA1, 1,195 BRCA2 and 19,178 assumed mutation-negative breast cancer cases (Table 3) indicated that TN tumor status is highly predictive of BRCA1 mutation status for women diagnosed at younger than 50 years (LR = 3.73; 95% CI, 3.43 to 4.05) and at age 50 years or older (LR = 4.41; 95% CI 3.86 to 5.04), and results were little different for unstratified analysis (see Additional file 1: Table S3, also displaying cell counts).