Table 1.
Demographic characteristics of participants of the Shanghai Breast Cancer Study (1996–2005) and Shanghai Breast Cancer Survival Study (2002–2006)
| Discovery Stage | Replication Stage | |
|---|---|---|
| No. of cases | 1,950 | 4,160 |
| Total no. of deaths | 331 | 388 |
| No. of recurrences | 411 | 504 |
| No. of breast cancer deaths | 299 | 331 |
| Age at diagnosis (median, range) | 48.3 (22.6–69.9) | 51.2 (20.4–75.0) |
| Year of follow-up (median) | 6.1 (0.3–8.7) | 3.7 (0.5–8.2) |
| TNM (%) | ||
| I | 29.88 | 35.83 |
| II | 59.07 | 53.39 |
| III | 10.03 | 10.24 |
| IV | 1.02 | 0.54 |
| ER status (%) | ||
| Positive | 63.71 | 64.34 |
| Negative | 36.29 | 35.66 |
| PR status(%) | ||
| Positive | 63.24 | 58.03 |
| Negative | 36.76 | 41.97 |
| Chemotherapy (%) | ||
| Yes | 94.2 | 91.69 |
| No | 5.8 | 8.31 |
| Radiotherapy (%) | ||
| Yes | 36.58 | 32.23 |
| No | 63.42 | 67.77 |
| Tamoxifen use (%) | ||
| Yes | 67.09 | 51.27 |
| No | 32.91 | 48.73 |
| Mastectomy (%) | ||
| Yes | 99.9 | 99.73 |
| No | 0.1 | 0.27 |
| 5-year survival rate (%) | 85.85 | 89.12 |
a
Patients with missing data were excluded.