Table 4. Association of oestrogen receptor α (ER-α) and ER-β serum bioactivity (controlled for each other) with risk of breast cancer; classification according to quintiles among controls.
|
Cases
|
||||||||
|---|---|---|---|---|---|---|---|---|
| Controls |
All
|
ER-negative
|
ER-positive
|
|||||
| Quintilea | Range (pg ml−1) | N (%) | N (%) | OR (95% CI)b | N (%) | OR (95% CI)b | N (%) | OR (95% CI)b |
| ER-α serum bioactivity | ||||||||
| 1st | 0–13.8 | 24 (19.2) | 24 (14.3) | 1.00 (ref.) | 4 (9.5) | 1.00 (ref.) | 20 (15.9) | 1.00 (ref.) |
| 2nd | 13.9–21.6 | 26 (20.8) | 25 (14.9) | 0.99 (0.44–2.27) | 7 (16.7) | 1.52 (0.38–6.16) | 18 (14.3) | 0.91 (0.38–2.22) |
| 3rd | 21.7–29.5 | 25 (20.0) | 23 (13.7) | 0.82 (0.35–1.91) | 12 (28.6) | 2.80 (0.73–10.67) | 11 (8.7) | 0.44 (0.17–1.18) |
| 4th | 29.6–42.0 | 25 (20.0) | 33 (19.6) | 1.07 (0.47–2.43) | 10 (23.8) | 2.02 (0.53–7.78) | 23 (18.3) | 0.94 (0.39–2.28) |
| 5th | ⩾42.1 | 25 (20.0) | 63 (37.5) | 2.24 (1.04–4.81) | 9 (21.4) | 1.80 (0.47–6.90) | 54 (42.9) | 2.43 (1.09–5.44) |
| P-valuec | P=0.01 | P=0.34 | P=0.007 | |||||
| ER-β serum bioactivity | ||||||||
| 1st–3rd | 0 | 80 (64.0) | 86 (51.2) | 1.00 (ref.) | 22 (52.4) | 1.00 (ref.) | 64 (50.8) | 1.00 (ref.) |
| 4th | 0.1–53 | 20 (16.0) | 21 (12.5) | 0.94 (0.45–1.96) | 4 (9.5) | 0.92 (0.27–3.14) | 17 (13.5) | 0.93 (0.42–2.06) |
| 5th | >53 | 25 (20.0) | 61 (36.3) | 2.32 (1.04–4.81) | 16 (38.1) | 2.12 (0.92–4.87) | 45 (35.7) | 2.36 (1.26–4.43) |
| P-valuec | P=0.008 | P=0.07 | P=0.01 | |||||
a
Quintiles according to distribution among controls.
b
Adjusted for age and other marker.
c
P-value for trend, adjusted for age and other marker.