Table 3. Preoperative patient characteristics and N stage after surgery in the specimens 1–2 true-positive and false-negative groups.
| Variable* | Specimens 1–2 | P value | |
|---|---|---|---|
| True-positive (n=129), No. (%) | False-negative (n=18), No. (%) | ||
| Age (years) | 50.3±10.3 | 51.7±11.2 | 0.59 |
| US tumor size | 0.93 | ||
| T1 | 18 (14.2) | 2 (11.1) | |
| T2 | 70 (55.1) | 10 (55.6) | |
| T3 | 39 (30.7) | 6 (33.3) | |
| US no. of suspicious LN | 0.53 | ||
| ≤3 | 72 (56.7) | 11 (64.7) | |
| ≥4 | 55 (43.3) | 6 (35.3) | |
| US long-axis of LN, cm | <0.001 | ||
| ≤1 | 11 (8.7) | 7 (38.9) | |
| 1–2 | 58 (45.7) | 9 (50.0) | |
| >2 | 58 (45.7) | 2 (11.1) | |
| US short-axis of LN, cm | <0.001 | ||
| ≤1 | 51 (40.2) | 17 (94.4) | |
| >1 | 76 (59.8) | 1 (5.6) | |
| US shape of LN | 0.37 | ||
| Regular | 114 (86.4) | 18 (100) | |
| Irregular | 13 (13.6) | 0 (0) | |
| US margin of LN | 1.00 | ||
| Circumscribed | 121 (95.3) | 18 (100) | |
| Not circumscribed | 6 (4.7) | 0 (0) | |
| US cortex of LN | 0.42 | ||
| No thickening | 3 (2.4) | 1 (5.6) | |
| Thickening | 124 (97.6) | 17 (94.4) | |
| US hilar of LN | 0.36 | ||
| Normal | 8 (6.3) | 2 (11.1) | |
| Compressed or displaced | 119 (93.7) | 16 (88.9) | |
| US blood flow of LN | 0.93 | ||
| Without NHBF | 86 (67.7) | 12 (66.7) | |
| NHBF | 41 (32.3) | 6 (33.3) | |
| CNB tumor pathology | 0.60 | ||
| Invasive ductal cancer | 104 (80.6) | 16 (88.9) | |
| Others | 25 (19.4) | 2 (11.1) | |
| CNB tumor grade | 1.00 | ||
| II | 54 (67.5) | 6 (66.7) | |
| III | 26 (32.5) | 3 (33.3) | |
| CNB hormone receptor status | 0.17 | ||
| Positive | 73 (73.0) | 14 (93.3) | |
| Negative | 27 (27.0) | 1 (6.7) | |
| CNB Ki67 status‡ | 0.07 | ||
| High | 97 (98.0) | 12 (85.7) | |
| Low | 2 (2.0) | 2 (14.3) | |
| CNB HER2 status | 1.00 | ||
| Positive | 39 (41.9) | 3 (37.5) | |
| Negative | 54 (58.1) | 5 (62.5) | |
| N stage | 0.17 | ||
| N0 | 24 (21.1) | 0 (0) | |
| N1 | 41 (36.0) | 7 (38.9) | |
| N2 | 28 (24.6) | 6 (33.3) | |
| N3 | 21 (18.4) | 5 (27.8) | |
Values in parentheses are percentages unless indicated otherwise. *, some data are missing; ‡, cut-off point 14%. IQR, interquartile range; US, ultrasound; LN, lymph node; NHBF, non-hilar blood flow; CNB, core needle biopsy; HER2, human epidermal growth factor receptor 2.