Table 1 Family histories* of all women under study (N = 1,987), of all women with breast cancer (n = 136) and of all women with breast cancer under the age of 50 (n = 73)
Presence of Family characteristics | All women | Women with breast cancer | |||
|---|---|---|---|---|---|
Breast cancer at any age | Log rank; P | Breast cancer under age 50 | Log rank; P | ||
N (%) | N (%) | N (%) | |||
Total | 1987 (100) | 136 (6.8) | 73 (3.7) | ||
≥ 2 cases of female breast cancer in first or second-degree relatives | 614 (30.9) | 54 (39.7) | 7.39; P = .007 | 31 (5.0) | 5.02; P = .03 |
≥ 2 cases of female breast cancer in first-degree relatives | 165 (8.3) | 20 (14.7) | 5.23; P = .02 | 13 (17.8) | 9.85; P = .002 |
≥ 1 case of female breast cancer under age 50 | 789 (39.7) | 52 (6.6) | 12.47; P = .0004 | 35 (4.4) | 7.85; P = .005 |
≥ 2 cases of female breast cancer under age 50 | 113 (5.7) | 10 (8.8) | 1.92; P = .17 | 10 (8.8) | 12.33; P = .0004 |
≥ 1 case of female breast cancer under age 40 | 231 (11.6) | 18 (7.8) | 12.01; P = .0005 | 12 (5.2) | 8.52; P = .004 |
≥ 2 cases of female breast cancer under age 40 | 10 (0.5) | - | - | - | - |
≥ 1 case of female breast cancer under age 30 | 33 (1.7) | 1 (3.0) | - | 1 (3.0) | - |
Male breast cancer | 12 (0.6) | 1 (8.0) | - | 1 (8.0) | - |
Bilateral breast cancer in affected sister (index patient) | 104 (5.2) | 16 (15.4) | 13.94; P = .0002 | 11 (10.6%) | 15.00; P = .0001 |
Ovarian cancer | 54 (2.7) | 5 (9.3) | 1.93; P = .16 | 3 (5.5%) | 1.23; P = .27 |
Breast and ovarian cancer in one person | 8 (0.4) | 2 (25.0) | 12.05; P = .0005 | 2 (25%) | 14.00; P = .0002 |
Prostate cancer under age 60 | 43 (2.1) | 1 (2.3) | 1 (2.3%) | ||
DCIS in affected sister (index patient) | 169 (8.5) | 15 (8.9) | 0.97; P = .32 | 7 (4.1%) | 0.04; P = .84 |