Table 1 Clinico-pathological features of breast cancers diagnosed in the lowest and highest quintiles of mammographic density.
Characteristics | Lowest quintile | Highest quintile | P value |
|---|---|---|---|
Invasive | 142 | 119 | |
Age at diagnosis | |||
Mean ± SD | 64.5 ± 7.0 | 61.5 ± 7.5 | 0.0007a |
Median | 65.5 | 61.4 | |
Range | 47–88 | 43–81 | |
Screening timing | |||
Lapsed screener | 2 (1%) | 1 (1%) | 0.0006b |
Interval cancer | 10 (7%) | 27 (23%) | |
Screen detected | 130 (92%) | 91 (76%) | |
Tumor size | |||
<20 mm | 80 (60%) | 57 (53%) | 0.3966b |
20–49 mm | 39 (30%) | 41 (38%) | |
≥50 mm | 13 (10%) | 10 (9%) | |
NA | 10 | 11 | |
Intrinsic subtype | |||
TNBC | 10 (7%) | 6 (6%) | 0.9450c |
ER−, Her2+ | 2 (1%) | 2 (2%) | |
Luminal Her2+ | 8 (6%) | 7 (7%) | |
Luminal | 114 (86%) | 90 (87%) | |
NA | 8 | 14 | |
Invasive cancer histology subtype | |||
Ductal | 117 (82%) | 91 (76%) | 0.3523b |
Lobular | 7 (5%) | 11 (10%) | |
Other invasive | 18 (13%) | 17 (14%) | |
Tumor grade | |||
G1 | 34 (26%) | 31 (29%) | 0.4003b |
G2 | 62 (47%) | 55 (51%) | |
G3 | 36 (27%) | 21 (20%) | |
NA | 10 | 12 | |
Nodal status | |||
Positive | 22 (21%) | 19 (20%) | >0.9999b |
Negative | 82 (79%) | 75 (80%) | |
NA | 38 | 25 | |
Proliferation index (Ki67) | |||
High (≥15%) | 19 (25%) | 23 (35%) | 0.1976b |
Low (<15%) | 58 (75%) | 42 (65%) | |
NA | 65 | 54 | |
First-degree relatives with breast cancer | |||
Yes | 39 (27%) | 46 (39%) | 0.0637b |
No | 103 (73%) | 73 (61%) | |
Strong family history of breast cancer | |||
Yes | 11 (8%) | 20 (17%) | 0.0336b |
No | 131 (92%) | 99 (83%) | |
