Table 1.
Clinical and ultrasonic characteristics of the PTC patients.
| Characteristics | Training set | Validation set (n = 330) | P value* | |||
|---|---|---|---|---|---|---|
| Total (n = 769) | CLNM+(n = 389) | CLNM−(n = 380) | P value | |||
| Sex | ||||||
| Male | 246 (32.0%) | 151 (38.8%) | 95 (25.0%) | 100 (30.3%) | ||
| Female | 523 (68.0%) | 238 (61.2%) | 285 (75.0%) | <0.001 | 230 (69.7%) | 0.581 |
| Age (Y) | ||||||
| ≥55 | 142 (18.5%) | 62 (15.9%) | 80 (21.1%) | 64 (19.4%) | ||
| <55 | 627 (81.5%) | 327 (84.1%) | 300 (78.9%) | 0.068 | 266 (80.6%) | 0.718 |
| BMI (kg/m2) | ||||||
| Normal | 32 (4.2%) | 21 (5.4%) | 11 (2.9%) | 12 (3.6%) | ||
| Overweight | 467 (60.7%) | 225 (57.8%) | 242 (63.7%) | 207 (62.7%) | ||
| Obesity | 270 (35.1%) | 143 (36.8%) | 127 (33.4%) | 0.101 | 111 (33.6%) | 0.797 |
| Diabetes | ||||||
| Absence | 677 (88.0%) | 349 (89.7%) | 328 (86.3%) | 288 (87.3%) | ||
| Presence | 92 (12.0%) | 40 (10.3%) | 52 (13.7%) | 0.146 | 42 (12.7%) | 0.723 |
| BRAF V600E mutation | ||||||
| Negative | 85 (11.1%) | 43 (11.1%) | 42 (11.1%) | 41 (12.4%) | ||
| Positive | 684 (88.9%) | 346 (88.9%) | 338 (88.9%) | 1.000 | 289 (87.6%) | 0.513 |
| CLT | ||||||
| Presence | 234 (30.4%) | 112 (28.8%) | 122 (32.1%) | 118 (35.8%) | ||
| Absence | 535 (69.6%) | 277 (71.2%) | 258 (67.9%) | 0.318 | 212 (64.2%) | 0.083 |
| Maximum tumor size (cm) | ||||||
| ≤1 | 470 (61.1%) | 176 (45.2%) | 294 (77.4%) | 208 (63.0%) | ||
| >1 to ≤2 | 201 (26.1%) | 141 (36.2%) | 60 (15.8%) | 87 (26.4%) | ||
| >2 to ≤4 | 80 (10.4%) | 58 (14.9%) | 22 (5.8%) | 28 (8.5%) | ||
| >4 | 18 (2.3%) | 14 (3.6%) | 4 (1.1%) | <0.001 | 7 (2.1%) | 0.788 |
| The number of foci | ||||||
| 1 | 513 (66.7%) | 226 (58.1%) | 287 (75.5%) | 230 (69.7%) | ||
| 2 | 188 (24.4%) | 123 (31.6%) | 65 (17.1%) | 72 (21.8%) | ||
| 3 or more | 68 (8.8%) | 40 (10.3%) | 28 (7.4%) | <0.001 | 28 (8.5%) | 0.603 |
| Bilaterality | ||||||
| Absence | 607 (78.9%) | 282 (72.5%) | 325 (85.5%) | 270 (81.8%) | ||
| Presence | 162 (21.1%) | 107 (27.5%) | 55 (14.5%) | <0.001 | 60 (18.2%) | 0.275 |
| Location | ||||||
| Middle/Lower | 516 (67.1%) | 311 (79.9%) | 205 (53.9%) | 235 (71.2%) | ||
| Upper | 253 (32.9%) | 78 (20.1%) | 175 (46.1%) | <0.001 | 95 (28.8%) | 0.179 |
| Nodular composition | ||||||
| Mixed cystic and solid | 7 (0.9%) | 4 (1.0%) | 3 (0.8%) | 5 (1.5%) | ||
| Solid | 762 (99.1%) | 385 (99.0%) | 377 (99.2%) | 0.727 | 325 (98.5%) | 0.376 |
| Echogenicity | ||||||
| Hyperechoic or isoechoic | 25 (3.3%) | 16 (4.1%) | 9 (2.4%) | 12 (3.6%) | ||
| Hyperechoic | 731 (95.1%) | 365 (93.8%) | 366 (96.3%) | 317 (96.1%) | ||
| Very hypoechoic | 13 (1.7%) | 8 (2.1%) | 5 (1.3%) | 0.280 | 1 (0.3%) | 0.164 |
| Shape | ||||||
| A/T ≤1 | 273 (35.5%) | 108 (27.8%) | 165 (43.4%) | 128 (38.8%) | ||
| A/T >1 | 496 (64.5%) | 281 (72.2%) | 215 (56.6%) | <0.001 | 202 (61.2%) | 0.299 |
| Margin | ||||||
| Smooth | 487 (63.3%) | 222 (57.1%) | 265 (69.7%) | 210 (63.6%) | ||
| Lobulated or irregular | 178 (23.1%) | 97 (24.9%) | 81 (21.3%) | 80 (24.2%) | ||
| ETE | 104 (13.5%) | 70 (18.0%) | 34 (8.9%) | <0.001 | 40 (12.1%) | 0.791 |
| Echogenic foci | ||||||
| None/large comet-tail artifacts | 234 (30.4%) | 87 (22.4%) | 147 (38.7%) | 104 (31.5%) | ||
| Macrocalcifications | 43 (5.6%) | 24 (6.2%) | 19 (5.0%) | 19 (5.8%) | ||
| Peripheral calcifications | 7 (0.9%) | 5 (1.3%) | 2 (0.5%) | 2 (0.6%) | ||
| Punctate echogenic foci | 485 (63.1%) | 273 (70.2%) | 212 (55.8%) | <0.001 | 205 (62.1%) | 0.938 |
| ETE detected during surgery | ||||||
| Absence | 628 (81.7%) | 275 (70.7%) | 353 (92.9%) | 284 (86.1%) | ||
| Presence | 141 (18.3%) | 114 (29.3%) | 27 (7.1%) | <0.001 | 46 (13.9%) | 0.075 |
| LLNM | ||||||
| Absence | 703 (91.4%) | 337 (86.6%) | 366 (96.3%) | 306 (92.7%) | ||
| Presence | 66 (8.6%) | 52 (13.4%) | 14 (3.7%) | <0.001 | 24 (7.3%) | 0.468 |
PTC, papillary thyroid carcinoma; Y, year; BMI, body mass index; CLT, chronic lymphocytic thyroiditis; A/T, aspect ratio (height divided by width on transverse views); ETE, extrathyroidal extension; CLNM, central lymph node metastasis; LLNM, lateral lymph node metastasis.
P value < 0.05 indicates a significant difference between CLNM+ and CLNM− group in the training set.
P value* < 0.05 indicates a significant difference between training and validation sets.