Table 2 Age-adjusted incidence rate (AAIR) of breast cancer, according to type of tumor and estrogen receptor (ER) status of invasive cancers among menopausal women in the California Teachers Study
Period | Woman | In situ | Invasive | ER positive | ER negative | ||||
|---|---|---|---|---|---|---|---|---|---|
| Â | years | n | AAIR (95% CI) | n | AAIR (95% CI) | n | AAIR (95% CI) | n | AAIR (95% CI) |
1996-99 | 208,860 | 207 | 95.2 (81.6-108.7) | 1072 | 501.7 (470.3-533.1) | 765 | 358.7 (332.1-385.3) | 127 | 59.5 (48.6-70.3) |
2000-02 | 158,917 | 197 | 113.7 (96.5-130.9) | 914 | 528.0 (491.1-564.9) | 676 | 390.6 (358.8-422.3) | 103 | 59.4 (46.9-71.9) |
2003-05 | 149,509 | 161 | 98.2 (79.1-117.3) | 682 | 390.6 (355.6-425.7) | 504 | 293.8 (261.9-325.7) | 94 | 51.0 (40.5-61.5) |
Total cases | Â | 565 | Â | 2668 | Â | 1945 | Â | 324 | Â |
% change 1996-99 to 2000-02 | Â | Â | 19.4% P = 0.09 | Â | 5.2% P = 0.30 | Â | 8.9% P = 0.13 | Â | -0.2% P = 0.99 |
% change 2000-02 to 2003-05 | Â | Â | -13.6% P = 0.24 | Â | -26.0% P < 0.001 | Â | -24.8% P < 0.001 | Â | -14.1% P = 0.38 |