Table 4.
Ultrasound image features for predicting malignant lymph nodes in the training and validation sets.
| Characteristics | Total (n = 1082) | Training set (n = 760) | Validation set (n = 322) | P value |
|---|---|---|---|---|
| Long-axis (median [IQR]) | 2.000 [1.500, 2.770] | 2.000 [1.500, 2.752] | 2.000 [1.555, 2.800] | 0.602 |
| Number of passes per node (median [IQR]) | 3.000 [2.000, 3.000] | 3.000 [2.000, 3.000] | 3.000 [2.000, 3.000] | 0.017 |
| Short-axis (%) | 0.390 | |||
| >1 cm | 882 (81.5%) | 614 (80.8%) | 268 (83.2%) | |
| ≤1 cm | 200 (18.5%) | 146 (19.2%) | 54 (16.8%) | |
| Long-axis/short-axis ratio (%) | 0.955 | |||
| ≥1.5 | 229 (21.2%) | 160 (21.1%) | 69 (21.4%) | |
| <1.5 | 853 (78.8%) | 600 (78.9%) | 253 (78.6%) | |
| Echo intensity (%) | 0.087 | |||
| Hyperechoic | 32 (3.0%) | 25 (3.3%) | 7 (2.2%) | |
| Hypoechoic | 1041 (96.2%) | 726 (95.5%) | 315 (97.8%) | |
| Isoechoic | 9 (0.8%) | 9 (1.2%) | 0 (0.00) | |
| Echogenicity (%) | 0.980 | |||
| Heterogeneous | 671 (62.0%) | 472 (62.1%) | 199 (61.8%) | |
| Homogeneous | 411 (38.0%) | 288 (37.9%) | 123 (38.2%) | |
| Margin (%) | 0.712 | |||
| Indistinct | 866 (80.0%) | 611 (80.4%) | 255 (79.2%) | |
| Distinct | 216 (20.0%) | 149 (19.6%) | 67 (20.8%) | |
| Blood flow (%) | 0.646 | |||
| Rich | 890 (82.3%) | 622 (81.8%) | 268 (83.2%) | |
| Lacking | 192 (17.7%) | 138 (18.2%) | 54 (16.8%) | |
| Fusion (%) | 0.268 | |||
| Absent | 822 (76.0%) | 585 (77.0%) | 237 (73.6%) | |
| Present | 260 (24.0%) | 175 (23.0%) | 85 (26.4%) | |
| Central hilar structure (CHS) (%) | 0.237 | |||
| Absent | 740 (68.4%) | 511 (67.2%) | 229 (71.1%) | |
| Present | 342 (31.6%) | 249 (32.8%) | 93 (28.9%) |