Table 1.
Patient characteristics and pathological parameters of the primary tumor by HER2 status.
| HER2 status according to ASCO/CAP 2018 | |||||||
|---|---|---|---|---|---|---|---|
| HER2 negative (n = 34) |
HER2 positive (n = 9) |
P | HER2 0 (n = 11) |
HER2-low (n = 23) | P | ||
| Mean (±SD) | 59.8 (±11.6) |
59.8 (±12.1) |
0.997* | 56.5 (±5.6) |
61.4 (±13.4) |
||
| Age at diagnosis | 0.251* | ||||||
| Mean (±SD) | 4.9 (±4.4) |
4.4 (±3.5) |
0.783* | 5.9 (±6.6) |
4.4 (±2.8) |
||
| Number of lymph nodes containing macrometastases |
0.352* | ||||||
| Range | 2–23 | 2–13 | 2–23 | 2–12 | |||
| Tumor size (mm) | Mean (±SD) | 31.8 (±20.4) |
40.1 (±18.5) |
0.274* | 32.1 (±22.0) |
31.6 (±20.2) |
0.950* |
| Range | 10–100 | 12–78 | 14–90 | 10–100 | |||
| Total extent, number of cases n (%) |
Extensive (≥40 mm) | 22 (64.7) |
7 (77.8) |
0.693† | 8 (72.7) |
14 (60.9) |
0.705† |
| Non- extensive | 12 (35.3) |
2 (22.2) |
3 (27.3) |
9 (39.1) |
|||
| Collective growth pattern, number of cases, n (%) |
Unifocal | 11 (32.4) |
2 (22.2) |
0.579† | 2 (18.2) |
9 (39.1) |
0.218† |
| Multifocal | 11 (32.4) |
2 (22.2) |
6 (54.5) |
5 (21.7) |
|||
| Diffuse | 12 (35.3) |
5 (55.6) |
3 (27.3) |
9 (39.1) |
|||
| Tumor grade, number of cases, n (%) |
Grade I | 3 (8.8) |
0 (0.0) |
0.724† | 1 (9.1) |
2 (8.7) |
0.734† |
| Grade II | 21 (61.8) |
5 (55.6) |
8 (72.7) |
13 (56.5) |
|||
| Grade III | 10 (29.4) |
4 (44.4) |
2 (18.2) |
8 (34.8) |
|||
| Molecular phenotype, number of cases, n (%) |
Luminal A- like | 10 (29.4) |
0 (0.0) |
<0.001† | 4 (36.4) |
6 (26.1) |
0.598† |
| Luminal B- like | 22 (64.7) |
0 (0.0) |
6 (54.5) |
16 (69.6) |
|||
| Triple negative | 2 (5.9) |
0 (0.0) |
1 (9.1) |
1 (4.3) |
|||
| HER2 | 0 (0.0) |
9 (100.0) |
0 (0.0) |
0 (0.0) |
|||
*Calculated using independent samples t-tests (student’s t-test).
†Calculated using Fisher’s exact test.