Table 2.
Association of automated assessment of Ki-67 extent of staining with clinicopathological characteristics
| Characteristic | Automated assessment of Ki-67 extent of staining | P | ||
|---|---|---|---|---|
| Low N (%) | Moderate N (%) | High N (%) | ||
| All tissue samples (N = 1334) * | 406 (30) | 446 (33) | 482 (36) | |
| Ki-67 expression (visual) | ||||
| High | 13 (3) | 102 (22) | 359 (76) | < 0.0001 |
| Moderate | 293 (41) | 314 (44) | 112 (16) | |
| Negative | 82 (83) | 15 (15) | 2 (2) | |
| Not available | 18 (43) | 15 (36) | 9 (21) | |
| Age at diagnosis (y) | ||||
| < 35 | 2 (6) | 13 (36) | 21 (58) | 0.0008 |
| 35-50 | 101 (28) | 120 (33) | 141 (39) | |
| 50-65 | 160 (36) | 133 (30) | 149 (34) | |
| >65 | 143 (29) | 180 (36) | 171 (35) | |
| Method of detection | ||||
| Mammography screening | 102 (41) | 81 (33) | 66 (27) | 0.0001 |
| Other | 298 (28) | 355 (34) | 403 (38) | |
| Not available | 6 (21) | 10 (34) | 13 (45) | |
| Primary tumour diameter (cm) | ||||
| < 0.5 | 8 (44) | 8 (44) | 2 (11) | < 0.0001 |
| 0.5-1 | 82 (42) | 66 (34) | 49 (25) | |
| 1-2 | 182 (34) | 180 (34) | 172 (32) | |
| 2-5 | 104 (22) | 156 (33) | 212 (45) | |
| > 5 | 13 (24) | 14 (25) | 28 (51) | |
| Not available | 17 (29) | 22 (38) | 19 (33) | |
| No. of positive axillary nodes | ||||
| 0 | 276 (35) | 253 (32) | 264 (33) | 0.0142 |
| 1-3 | 80 (27) | 98 (33) | 119 (40) | |
| 4-9 | 26 (23) | 45 (40) | 41 (37) | |
| ≥ 10 | 5 (16) | 11 (35) | 15 (48) | |
| Not available | 19 (19) | 39 (39) | 43 (43 | |
| Histological grade | ||||
| 1 | 118 (52) | 73 (32) | 37 (16) | < 0.0001 |
| 2 | 122 (26) | 184 (39) | 171 (36) | |
| 3 | 34 (12) | 67 (23) | 188 (65) | |
| Not available | 132 (39) | 122 (36) | 86 (25) | |
| Histological type | ||||
| Ductal | 275 (27) | 342 (34) | 402 (40) | < 0.0001 |
| Lobular | 87 (46) | 67 (35) | 36 (19) | |
| Special | 44 (35) | 37 (30) | 44 (35) | |
| ER expression | ||||
| Positive | 301 (35) | 324 (38) | 234 (27) | < 0.0001 |
| Negative | 69 (17) | 102 (26) | 228 (57) | |
| Not available | 36 (47) | 20 (26) | 20 (26) | |
| PR expression | ||||
| Positive | 254 (37) | 270 (39) | 171 (25) | < 0.0001 |
| Negative | 122 (21) | 151 (27) | 295 (52) | |
| Not available | 30 (42) | 25 (35) | 16 (23) | |
| HER2 amplification | ||||
| Positive | 34 (14) | 75 (31) | 134 (55) | < 0.0001 |
| Negative | 331 (33) | 333 (34) | 327 (33) | |
| Not available | 41 (41) | 38 (38) | 21 (21) | |
| HER2 expression | ||||
| Positive | 26 (13) | 60 (29) | 121 (58) | < 0.0001 |
| Negative | 333 (33) | 340 (34) | 324 (33) | |
| Not available | 47 (36) | 46 (35) | 37 (28) | |
| p53 expression | ||||
| High | 16 (7) | 50 (22) | 158 (71) | < 0.0001 |
| Moderate | 98 (27) | 135 (37) | 129 (36) | |
| Low | 222 (39) | 196 (34) | 155 (27) | |
| Not available | 70 (40) | 65 (37) | 40 (23) | |
| Molecular subtype | ||||
| Basal | 11 (12) | 15 (16) | 69 (73) | < 0.0001 |
| HER2+/HR- | 14 (12) | 33 (28) | 70 (60) | |
| Luminal A | 291 (38) | 288 (37) | 191 (25) | |
| Luminal B | 19 (16) | 37 (32) | 60 (52) | |
| Five-marker negative | 8 (19) | 6 (14) | 28 (67) | |
| Unclassified | 9 (16) | 18 (32) | 29 (52) | |
| Not available | 54 (39) | 49 (36) | 35 (25) | |
* due to ties the number of samples in each tertile is not equal