Table 2.
Odds ratios (ORs) and 95% confidence intervals (CIs) for breast cancer risk by tumor subtype associated with BI-RADS-measured mammographic density
| |
Number of subjects |
Cases versus controls |
|
Triple-negatives versus controls |
|||
|---|---|---|---|---|---|---|---|
| |
Controls |
Cases |
Model 1
a
|
Model 2
b
|
TN cases, n |
Model 1 |
Model 2 |
| OR (95% CI) | OR (95% CI) | OR (95% CI) | OR (95% CI) | ||||
| Almost entirely fat |
25 |
13 |
1.00 (Referent) |
0.48 (0.22, 1.08) |
1 |
1.00 (Referent) |
0.17 (0.02, 1.43) |
| Scattered fibroglandular densities |
197 |
183 |
2.07 (0.93, 4.59) |
1.00 (Referent) |
31 |
5.96 (0.70, 50.64) |
1.00 (Referent) |
| Heterogeneously dense |
253 |
232 |
2.06 (0.92, 4.60) |
1.00 (0.7, 1.35) |
40 |
5.83 (0.68, 50.04) |
0.98 (0.5, -1.75) |
| Extremely dense |
53 |
63 |
2.45 (0.99, 6.09) |
1.19 (0.72, 1.95) |
12 |
7.13 (0.74, 68.90) |
1.20 (0.49, 2.90) |
| |
|
|
Ptrend = 0.24c |
|
Ptrend = 0.31 |
||
| |
|
|
Basal-like versus controls |
|
Luminal A versus controls |
||
| |
BL cases, n |
|
Model 1 |
Model 2 |
LA cases, n |
Model 1 |
Model 2 |
| |
|
|
OR (95% CI) |
OR (95% CI) |
|
OR (95% CI) |
OR (95% CI) |
| Almost entirely fat |
1 |
|
1.00 (Referent) |
0.29 (0.03, 2.51) |
4 |
1.00 (Referent) |
0.49 (0.15, 1.59) |
| Scattered fibroglandular densities |
19 |
|
3.45 (0.40, 29.90) |
1.00 (Referent) |
69 |
2.03 (0.63, 6.59) |
1.00 (Referent) |
| Heterogeneously dense |
22 |
|
3.03 (0.34, 26.67) |
0.88 (0.43, 1.80) |
86 |
2.09 (0.64, 6.79) |
1.03 (0.68, 1.56) |
| Extremely dense |
6 |
|
3.58 (0.34, 37.97) |
1.04 (0.34, 3.17) |
22 |
1.98 (0.54, 7.34) |
0.98 (0.50, 1.92) |
| Ptrend = 0.67 | Ptrend = 0.60 | ||||||
aModel 1 is adjusted for age, race, body mass index, menopausal status, family history of breast cancer, age at menarche, use of hormone therapy, and parity and age at first full-term pregnancy combined, where BI-RADS category 1 (almost entirely fat) is the referent group; bModel 2 is adjusted for the same variables as Model 1 but BI-RADS category 2 (scattered fibroglandular densities) is the referent group; cP-value for trend test is based on the likelihood ratio test statistic and is two-sided. The same ordinal model was fit to assess the P-value for trend of Model 1 and Model 2. BI-RADS, Breast Imaging Reporting and Data System; TN, triple-negative; BL, basal-like; LA, luminal-A; n, number of subjects.