Table 1.

Demographic characteristics of participants of the Shanghai Breast Cancer Study (1996–2005) and Shanghai Breast Cancer Survival Study (2002–2006)

Discovery stageReplication stage
No. of cases1,9504,160
Total no. of deaths331388
No. of recurrences411504
No. of breast cancer deaths299331
Age at diagnosis, median (range), y48.3 (22.6–69.9)51.2 (20.4–75.0)
Year of follow-up, median (range)6.1 (0.3–8.7)3.7 (0.5–8.2)
TNM (%)
 I29.8835.83
 II59.0753.39
 III10.0310.24
 IV1.020.54
ER status (%)
 Positive63.7164.34
 Negative36.2935.66
PR status (%)
 Positive63.2458.03
 Negative36.7641.97
Chemotherapy (%)
 Yes94.291.69
 No5.88.31
Radiotherapy (%)
 Yes36.5832.23
 No63.4267.77
Tamoxifen use (%)
 Yes67.0951.27
 No32.9148.73
Mastectomy (%)
 Yes99.999.73
 No0.10.27
5-y survival rate (%)85.8589.12

NOTE: Patients with missing data were excluded.