Table 1.
Patients and tumor characteristics according to mammographic density at baseline
| Total cohort | BI-RADS a | BI-RADS b | BI-RADS c | BI-RADS d | |
|---|---|---|---|---|---|
| Overall | 495 | 25 | 192 | 226 | 52 |
| Age, median (IQR) | 53 (45 to 63) | 59 (56 to 68) | 58 (48 to 66) | 50 (42 to 60) | 46 (40 to 57) |
| BMI, median (IQR) | 25 (23 to 29) | 31 (28 to 36) | 26 (24 to 29) | 24 (22 to 27) | 23 (21 to 26) |
| Tumor size (mm), median (IQR) | 30 (22 to 40) | 33 (24 to 39) | 29 (20 to 38) | 33 (24 to 43) | 33 (21 to 40) |
| Menopausal status | |||||
| Premenopausal | 269 (54.3%) | 6 (24.0%) | 78 (40.6%) | 149 (65.9%) | 36 (69.2%) |
| Postmenopausal | 226 (45.7%) | 19 (76.0%) | 114 (59.4%) | 77 (34.1%) | 16 (30.8%) |
| Any births | |||||
| No children | 69 (13.9%) | 2 (8.0%) | 18 (9.4%) | 40 (17.7%) | 9 (17.3%) |
| 1 or more children | 425 (85.9%) | 23 (92.0%) | 173 (90.1%) | 186 (82.3%) | 43 (82.7%) |
| Missing | 1 (0.2%) | 0 (0.0%) | 1 (0.5%) | 0 (0.0%) | 0 (0.0%) |
| Ever hormone replacement therapy | |||||
| Yes | 64 (12.9%) | 4 (16.0%) | 31 (16.1%) | 25 (11.1%) | 4 (7.7%) |
| No | 427 (86.3%) | 21 (84.0%) | 157 (81.8%) | 201 (88.9%) | 48 (92.3%) |
| Missing | 4 (0.8%) | 0 (0.0%) | 4 (2.1%) | 0 (0.0%) | 0 (0.0%) |
| ER | |||||
| Positive (> 10%) | 299 (60.4%) | 10 (40.0%) | 113 (58.9%) | 138 (61.1%) | 38 (73.1%) |
| Negative (≤ 10%) | 187 (37.8%) | 15 (60.0%) | 75 (39.1%) | 83 (36.7%) | 14 (26.9%) |
| Missing | 9 (1.8%) | 0 (0.0%) | 4 (2.1%) | 5 (2.2%) | 0 (0.0%) |
| PR | |||||
| Positive (> 10%) | 238 (48.1%) | 10 (40.0%) | 81 (42.2%) | 117 (51.8%) | 30 (57.7%) |
| Negative (≤ 10%) | 247 (49.9%) | 15 (60.0%) | 107 (55.7%) | 103 (45.6%) | 22 (42.3%) |
| Missing | 10 (2.0%) | 0 (0.0%) | 4 (2.1%) | 6 (2.7%) | 0 (0.0%) |
| HER2 | |||||
| Positive | 141 (28.5%) | 7 (28.0%) | 64 (33.3%) | 56 (24.8%) | 14 (26.9%) |
| Negative | 338 (68.3%) | 16 (64.0%) | 121 (63.0%) | 163 (72.1%) | 38 (73.1%) |
| Missing | 16 (3.2%) | 2 (8.0%) | 7 (3.6%) | 7 (3.1%) | 0 (0.0%) |
| Ki67 | |||||
| High (> 20%) | 381 (77.0%) | 21 (84.0%) | 152 (79.2%) | 167 (73.9%) | 41 (78.8%) |
| Low (≤ 20%) | 54 (10.9%) | 2 (8.0%) | 17 (8.9%) | 32 (14.2%) | 3 (5.8%) |
| Missing | 60 (12.1%) | 2 (8.0%) | 23 (12.0%) | 27 (11.9%) | 8 (15.4%) |
| St. Gallen | |||||
| Luminal A like | 47 (9.5%) | 1 (4.0%) | 16 (8.3%) | 28 (12.4%) | 2 (3.8%) |
| Luminal B like | 148 (29.9%) | 5 (20.0%) | 56 (29.2%) | 66 (29.2%) | 21 (40.4%) |
| HER2 positive | 141 (28.5%) | 7 (28.0%) | 64 (33.3%) | 56 (24.8%) | 14 (26.9%) |
| Triple negative | 121 (24.4%) | 9 (36.0%) | 42 (21.9%) | 62 (27.4%) | 8 (15.4%) |
| Missing | 38 (7.7%) | 3 (12.0%) | 14 (7.3%) | 14 (6.2%) | 7 (13.5%) |
| Lymph node status | |||||
| Negative | 79 (16.0%) | 3 (12.0%) | 30 (15.6%) | 39 (17.3%) | 7 (13.5%) |
| Positive | 334 (67.5%) | 17 (68.0%) | 131 (68.2%) | 148 (65.5%) | 38 (73.1%) |
| Missing | 82 (16.6%) | 5 (20.0%) | 31 (16.1%) | 39 (17.3%) | 7 (13.5%) |