Table 1.
Patient and tumor characteristics
| Characteristic | Chemotherapy | No chemotherapy | P-value |
|---|---|---|---|
| (n = 3703) | (n = 232) | ||
| Age, years | |||
| Mean (range) | 55.6 (20–100) | 58.3 (27–87) | 0.0008 |
| < 60, n (%) | 2298 (62) | 128 (55) | |
| 60– 69, n (%) | 971 (26) | 58 (25) | |
| ≥ 70, n (%) | 461 (12) | 46 (20) | |
| ECOG performance status, n (%) | |||
| 0 | 2301 (63) | 108 (47) | <0.0001 |
| 1 | 1298 (35) | 113 (50) | |
| 2–4 | 61 (2) | 7 (3) | |
| Primary tumor stage, n (%) | |||
| pT1/is | 1750 (50) | 114 (51) | 0.73 |
| pT2-4 | 1776 (50) | 110 (49) | |
| Lymph node stage, n (%) | |||
| pN0 | 1936 (52) | 126 (54) | |
| pN1 | 1003 (27) | 53 (23) | |
| pN2 | 411 (11) | 28 (12) | |
| pN3 | 259 (7) | 13 (6) | |
| NX | 82 (2) | 12 (5) | |
| No. of nodes involved, mean ± SD | 2.2 ± 4.7 | 2.3 ± 5.1 | 0.63 |
| Grading, n (%) | |||
| Grade 1/2 | 1731 (47) | 123 (55) | 0.028 |
| Grade 3 | 1927 (53) | 101 (45) | |
| Hormone-receptor status, n (%) | |||
| ER positive | 2217 (60) | 145 (62) | |
| PgR positive | 1857 (50) | 133 (57) | |
| Either ER or PgR positive | 2332 (63) | 156 (67) | 0.20 |
| Additional adjuvant treatment, n (%) | |||
| Endocrine therapy | 2079 (56) | 131 (56) | 0.99 |
| Radiotherapy | 2897 (78) | 146 (63) | <0.0001 |
Total patient numbers may deviate from n = 3935 because of missing values for some characteristics
ECOG Eastern Cooperative Oncology Group, ER estrogen receptor, PgR progesterone receptor, SD standard deviation