From: High-throughput mammographic-density measurement: a tool for risk prediction of breast cancer
Characteristic | Cases (n= 1,498) | Controls (n= 1,495) | P |
---|---|---|---|
Median | |||
Percentage density (%) | 16.9 | 11.0 | <0.001 |
Absolute dense area (cm2) | 24.3 | 16.9 | <0.001 |
Mean (SD) | |||
Age at diagnosis or reference date (y) | 61.2 (7.1) | 62.8 (6.9) | <0.001 |
Age at mammogram (y) | 60.6 (7.2) | 62.8 (6.7) | <0.001 |
Age at menarche (y) | 13.5 (1.4) | 13.6 (1.4) | 0.084 |
Age at menopause (y) | 50.6 (3.8) | 50.0 (3.9) | 0.001 |
BMI at diagnosis or reference date (kg/m2) | 25.1 (3.6) | 25.2 (3.9) | 0.801 |
Alcohol consumption (g/day) | 2.8 (5.0) | 2.3 (4.2) | 0.008 |
Percentage density (%) | 20.7 (16.1) | 15.7 (14.5) | <0.001 |
Absolute dense area (cm2) | 30.2 (23.7) | 23.3 (21.5) | <0.001 |
Frequency, number (%) | |||
Categoric percentage density (%) | <0.001 | ||
<10 | 477 (31.8) | 680 (45.5) | |
10-24 | 538 (35.9) | 506 (33.8) | |
25-49 | 384 (25.6) | 250 (16.7) | |
50-74 | 96 (6.4) | 57 (3.8) | |
≥75 | 3 (0.2) | 2 (0.1) | |
Categoric absolute dense area (cm2) | <0.001 | ||
<10 | 288 (19.2) | 475 (31.8) | |
10-24 | 471 (31.4) | 509 (34.0) | |
25-49 | 460 (30.7) | 347 (23.2) | |
50-74 | 211 (14.1) | 114 (7.6) | |
75-99 | 47 (3.1) | 39 (2.6) | |
≥100 | 21 (1.4) | 11(0.7) | |
Parity and age at first birth | <0.001 | ||
Nulliparous | 190 (12.7) | 148 (9.9) | |
1-3 children, age at first birth <25 y | 556 (37.1) | 555 (37.1) | |
1-3 children, age at first birth 25-29 y | 420 (28.0) | 399 (26.7) | |
1-3 children, age at first birth ≥30 y | 223 (14.9) | 212 (14.2) | |
≥4 children, age at first birth <25 y | 29 (1.9) | 31 (2.1) | |
≥4 children, age at first birth ≥25 y | 78 (5.2) | 150 (10.0) | |
Hormone replacement therapy | <0.001 | ||
Never used hormones | 722 (48.2) | 844 (56.5) | |
Ever used hormones | 774 (51.7) | 649 (43.4) | |
Unknown status of hormone use | 2 (0.1) | 2 (0.1) | |
Family history of breast cancer (ever) | 207 (13.8) | 119 (8.0) | <0.001 |
Benign breast disease (ever) | 351 (23.4) | 141 (9.4) | <0.001 |