Table 1. Clinicopathological characteristics of all three cohorts.
| Parameter | Cohort 1, N (%) | Cohort 2, N (%) | Cohort 3, N (%) |
|---|---|---|---|
| All patients | 461 | 279 | 795 |
| Year of diagnosis | 1962–1982 | 1976–2005 | 2000–2003 |
|
Age (years) | |||
| <50 | 127 (27.5) | 94 (33.7) | 270 (34) |
| ⩾50 | 334 (72.5) | 185 (66.3) | 525 (66) |
| Unknown | 0 | 0 | 0 |
|
Nodal status | |||
| Positive | 243 (52.7) | 59 (21.1) | 304 (38.2) |
| Negative | 201 (43.6) | 157 (56.3) | 469 (59) |
| Unknown | 17 (3.7) | 63 (22.6) | 22 (2.78) |
|
Tumour size | |||
| ⩽2 cm | 193 (41.9) | 187 (56.9) | 412 (51.8) |
| >2–5 cm | 177 (38.4) | 72 (35.9) | 343 (43.1) |
| >5 cm | 53 (11.5) | 0 (0) | 26 (3.3) |
| Unknown | 38 (8.2) | 19 (7.2) | 14 (1.8) |
|
ERα (path) | |||
| Positive (1–3) | 239 (51.8) | 142 (50.9) | 488 (61.4) |
| Negative (0) | 209 (45.3) | 97 (34.8) | 285 (35.8) |
| Unknown | 13 (2.8) | 40 (14.3) | 22 (2.8) |
|
PR (path) | |||
| Positive (1–3) | 221 (47.9) | 127 (45.5) | 403 (50.6) |
| Negative (0) | 211 (45.8) | 102 (36.6) | 371 (46.6) |
| Unknown | 29 (6.3) | 50 (17.9) | 22 (2.8) |
|
HER2 (IHC) | |||
| Positive (3) | 45 (9.8) | 17 (6.1) | 72 (9.1) |
| Negative (0–2) | 397 (86.1) | 216 (77.4) | 566 (71.2) |
| Unknown | 19 (4.1) | 46 (16.5) | 157 (19.7) |
|
Follow-up (m) | |||
| Median (range) | 105.46 (2.39–498.03 ) | 121 (7–385) | 114.84 (3.6–147.96) |
Abbreviations: ERα=estrogen receptor alpha; Her2=human epidermal growth factor receptor 2; IHC=immunohistochemistry; m=months; N=number; PR=progesterone receptor.