Table 3.
Characteristics of the study population according to the proportion of S100A8 staining tumor epithelial cells
| Study Population | Cytoplasmic S100A8 staining | |||||
|---|---|---|---|---|---|---|
| < 1% | ≥ 1%, < 10% | ≥ 10% | p-value (χ2) | |||
| N (%) | 498 | 420 (84) | 47 (9) | 31 (6) | ||
| Mean age at diagnosis, years (SD) | 75.9 (8.5) | 75.5 (8.4) | 76.3 (8.4) | 79.9 (9.5) | ||
| Mean follow-up after diagnosis, years (SD) | 9.2 (7.1) | 9.6 (7.1) | 8.3 (6.7) | 4.7 (4.9) | ||
| Deaths from BC (%) | 167 (34) | 134 (32) | 14 (30) | 19 (61) | ||
| Deaths from other causes (%) | 279 (56) | 241 (58) | 26 (55) | 12 (39) | ||
| Grade (%) | ||||||
| 1 | 54 (11) | 52 (12) | 2 (4) | 0 (0) | < 0.001 | |
| 2 | 287 (58) | 261 (62) | 19 (40) | 7 (23) | ||
| 3 | 155 (31) | 105 (25) | 26 (55) | 24 (77) | ||
| Lymph node metastasis (%) | ||||||
| Yes | 169 (34) | 134 (32) | 22 (47) | 9 (29) | 0.08 | |
| No | 226 (45) | 198 (47) | 19 (40) | 13 (42) | ||
| Unknown histology | 103 (21) | 88 (21) | 6 (13) | 9 (29) | ||
| Molecular subtype (%) | ||||||
| Luminal A | 268 (54) | 247 (59) | 17 (36) | 4 (13) | < 0.001 | |
| Luminal B (HER2-) | 116 (23) | 106 (25) | 8 (17) | 2 (7) | ||
| Luminal B (HER2+) | 36 (7) | 30 (7) | 5 (11) | 1 (3) | ||
| HER2 type | 28 (6) | 12 (3) | 8 (17) | 8 (27) | ||
| 5NP | 12 (2) | 4 (1) | 5 (11) | 3 (10) | ||
| BP | 35 (7) | 19 (5) | 4 (9) | 12 (40) | ||
| Histologic subtype (%) | ||||||
| Ductal (NOS) | 351 (70) | 294 (70) | 35 (75) | 22 (71) | 0.4 | |
| Lobular | 65 (13) | 60 (14) | 3 (6) | 2 (6) | ||
| Other | 82 (16) | 66 (16) | 9 (19) | 7 (23) | ||
| Ki67 high / low (%) | ||||||
| Ki67 < 15% | 301 (60) | 268 (64) | 25 (53) | 8 (26) | < 0.001 | |
| Ki67 ≥ 15% | 194 (39) | 150 (36) | 22 (47) | 22 (71) | ||
| Mitoses / 10 HPF, median (IQR p25, p75) | 5 (1, 12) | 4 (1, 9) | 9 (2, 16) | 14 (8, 21) | ||
| Mitoses / 10 HPF, quartiles (%) | ||||||
| ≤ 1 | 136 (27) | 127 (30) | 7 (15) | 2 (6) | < 0.001 | |
| > 1, ≤ 5 | 134 (27) | 121 (29) | 9 (19) | 4 (13) | ||
| > 5, ≤ 12 | 116 (23) | 94 (22) | 13 (28) | 9 (29) | ||
| > 12 | 112 (22) | 78 (19) | 18 (38) | 15 (48) | ||
| Number of infiltrating S100A8 + PMN cells (%) | ||||||
| < 10 | 405 (81) | 342 (81) | 38 (81) | 25 (81) | 0.99 | |
| ≥ 10 | 93 (19) | 78 (19) | 9 (19) | 6 (19) | ||
N number of patients, SD standard deviation, BC breast cancer, HER2 human epidermal growth factor receptor 2, 5NP 5 negative phenotype, BP basal phenotype, HPF high-power field, IQR interquartile range