Table 2. Baseline demographic and disease characteristics after propensity score matching.
| Characteristic | Overall (n=654) | BUS (n=327) | SLN-CEUS (n=327) | P value* |
|---|---|---|---|---|
| Age, mean (SD) | 49.60 (11.26) | 49.53 (11.38) | 49.68 (11.15) | 0.862 |
| Patients underwent NAT, n (%†) | 207 (31.65) | 98 (29.97) | 109 (33.33) | 0.401 |
| T stage, n (%) | 0.875 | |||
| 0 | 127 (19.42) | 59 (18.04) | 68 (20.80) | |
| 1 | 405 (61.93) | 207 (63.30) | 198 (60.55) | |
| 2 | 110 (16.82) | 56 (17.13) | 54 (16.51) | |
| 3 | 5 (0.76) | 2 (0.61) | 3 (0.92) | |
| 4 | 7 (1.07) | 3 (0.92) | 4 (1.22) | |
| N stage, n (%) | 0.604 | |||
| 0 | 510 (77.98) | 262 (80.12) | 248 (75.84) | |
| 1 | 89 (13.61) | 40 (12.23) | 49 (14.98) | |
| 2 | 45 (6.88) | 20 (6.12) | 25 (7.64) | |
| 3 | 10 (1.53) | 5 (1.53) | 5 (1.53) | |
| Tumor stage group, n (%) | 0.768 | |||
| 0 | 121 (18.50) | 58 (17.74) | 63 (19.27) | |
| I | 318 (48.62) | 165 (50.46) | 153 (46.79) | |
| II | 160 (24.46) | 79 (24.16) | 81 (24.77) | |
| III | 55 (8.41) | 25 (7.65) | 30 (9.17) |
*, P values are from the t-test, comparing BUS group and SLN-CEUS group; †, percentages are rounded to 2 decimal places. BUS, B-mode ultrasound; SLN-CEUS, contrast-enhanced ultrasound of sentinel lymph node; NAT, neoadjuvant treatment.