Table 2.
Factors associated with involvement of three or more ALNs
| Variable | Three or more LN (+) (%) | Two or less LN (+) (%) | p-value |
|---|---|---|---|
| Age (yr) | 49.2 | 50.6 | 0.053 |
| Tumor size by preoperative US (cm) | 2.66±1.07 | 2.23±1.0 | < 0.001 |
| Tumor size by MRI (cm) | 2.86±1.58 | 2.17±1.46 | < 0.001 |
| US tumor size (cm) | |||
| ≤ 2 | 68 (33.3) | 851 (49.7) | < 0.001 |
| > 2-5 | 136 (66.7) | 862 (50.3) | |
| Axillary US classification | |||
| Gr 1 | 11 (5.4) | 646 (37.7) | < 0.001 |
| Gr 2 | 34 (16.7) | 660 (38.5) | |
| Gr 3 | 38 (18.6) | 254 (14.8) | |
| Gr 4 | 57 (27.9) | 102 (6.0) | |
| Gr 5 | 62 (30.4) | 43 (2.5) | |
| Chest CT ALN | |||
| Positive | 106 (52.7) | 92 (5.4) | < 0.001 |
| Negative | 95 (47.3) | 1,621 (94.6) | |
| PET-CT ALN | |||
| Positive | 34 (79.1) | 71 (22.1) | < 0.001 |
| Negative | 9 (20.9) | 250 (77.9) | |
| Estrogen receptor | |||
| Positive | 134 (67.3) | 1,221 (71.9) | 0.177 |
| Negative | 65 (32.7) | 477 (28.1) | |
| Progesterone receptor | |||
| Positive | 125 (62.2) | 991 (58.3) | 0.289 |
| Negative | 76 (37.8) | 709 (41.7) | |
| HER2 receptor | |||
| Positive | 34 (17.0) | 223 (13.5) | 0.171 |
| Negative | 166 (83.0) | 1,434 (86.5) |
Values are presented as mean±standard deviation or number (%). ALN, axillary lymph node; LN, lymph node; US, ultrasonography; MRI, magnetic resonance imaging; CT, computed tomography; PET, positron emission tomography; HER2, human epidermal growth factor receptor 2.