TABLE 2.
Clinical and radiographic features of the patients
| Variables | Training cohort | Validation cohort | ||||
|---|---|---|---|---|---|---|
| Ki‐67 (−) (n = 366) | Ki‐67 (+) (n = 171) | p value | Ki‐67 (−) (n = 158) | Ki‐67 (+) (n = 74) | p value | |
| Gender | ||||||
| Male | 130 (35.5) | 78 (45.6) | 0.025 | 51 (32.3) | 24 (32.4) | 0.980 |
| Female | 236 (64.5) | 93 (54.4) | 107 (67.7) | 50 (67.6) | ||
| Age (years, average ± SD) | 54.5 ± 9.1 | 56.6 ± 9.0 | 0.013 | 54.6 ± 10.0 | 55.7 ± 9.6 | 0.389 |
| Having respiratory symptoms | ||||||
| Yes | 40 (10.9) | 19 (11.1) | 0.950 | 14 (8.9) | 12 (16.2) | 0.098 |
| No | 326 (89.1) | 152 (88.9) | 144 (91.1) | 62 (83.8) | ||
| BMI index | 24.2 ± 2.9 | 24.4 ± 2.8 | 0.418 | 24.4 ± 3.2 | 23.9 ± 3.2 | 0.350 |
| Smoking | ||||||
| Yes | 54 (14.8) | 34 (19.9) | 0.135 | 17 (10.8) | 12 (16.2) | 0.241 |
| No | 312 (85.2) | 137 (80.1) | 141 (89.2) | 62 (83.8) | ||
| Smoking index (pack‐year) | 532.5 ± 377.0 | 659.3 ± 507.8 | 0.359 | 750.3 ± 623.5 | 614.6 ± 466.2 | 0.679 |
| Former lung cancer history | ||||||
| Yes | 9 (2.5) | 2 (1.2) | 0.516 | 1 (0.6) | 0 (0) | 1.000 |
| No | 357 (97.5) | 169 (98.8) | 157 (99.4) | 74 (100) | ||
| Former malignancy history except lung cancer | ||||||
| Yes | 20 (5.5) | 6 (3.5) | 0.325 | 4 (2.5) | 6 (8.1) | 0.078 |
| No | 346 (94.5) | 165 (96.5) | 154 (97.5) | 68 (91.9) | ||
| Family history of lung cancer | ||||||
| Yes | 42 (11.5) | 15 (8.8) | 0.343 | 19 (12) | 5 (6.8) | 0.219 |
| No | 324 (88.5) | 156 (91.2) | 139 (88) | 69 (93.2) | ||
| Family history of malignancy except lung cancer | ||||||
| Yes | 65 (17.8) | 20 (11.7) | 0.073 | 20 (12.7) | 13 (17.6) | 0.318 |
| No | 301 (82.2) | 151 (88.3) | 138 (87.3) | 61 (82.4) | ||
| Abnormal tumor biomarker results | ||||||
| Yes | 59 (16.1) | 24 (14) | 0.533 | 19 (12) | 12 (16.2) | 0.382 |
| No | 307 (83.9) | 147 (86) | 139 (88) | 62 (83.8) | ||
| Multiple nodules | ||||||
| Yes | 177 (48.4) | 82 (48) | 0.930 | 75 (47.5) | 38 (51.4) | 0.581 |
| No | 189 (51.6) | 89 (52) | 83 (52.5) | 36 (48.6) | ||
| Nodule density | ||||||
| Pure GGO | 234 (63.9) | 101 (59.1) | 0.278 | 102 (64.6) | 41 (55.4) | 0.182 |
| Mixed GGO | 132 (36.1) | 70 (40.9) | 56 (35.4) | 33 (44.6) | ||
| Border | ||||||
| Unclear | 87 (23.8) | 50 (29.2) | 0.176 | 43 (27.2) | 20 (27) | 0.976 |
| Clear | 279 (76.2) | 121 (70.8) | 115 (72.8) | 54 (73) | ||
| Lobulation sign | ||||||
| Yes | 100 (27.3) | 59 (34.5) | 0.090 | 39 (24.7) | 24 (32.4) | 0.216 |
| No | 266 (72.7) | 112 (65.5) | 119 (75.3) | 50 (67.6) | ||
| Spiculation sign | ||||||
| Yes | 43 (11.7) | 37 (21.6) | 0.003 | 22 (13.9) | 16 (21.6) | 0.140 |
| No | 323 (88.3) | 134 (78.4) | 136 (86.1) | 58 (78.4) | ||
| Pleural indentation sign | ||||||
| Yes | 48 (13.1) | 35 (20.5) | 0.028 | 18 (11.4) | 14 (18.9) | 0.121 |
| No | 318 (86.9) | 136 (79.5) | 140 (88.6) | 60 (81.1) | ||
| Bubble sign | ||||||
| Yes | 56 (15.3) | 40 (23.4) | 0.023 | 23 (14.6) | 12 (16.2) | 0.742 |
| No | 310 (84.7) | 131 (76.6) | 135 (85.4) | 62 (83.8) | ||
| Vessel change | ||||||
| Yes | 83 (22.7) | 45 (26.3) | 0.357 | 25 (15.8) | 16 (21.6) | 0.280 |
| No | 283 (77.3) | 126 (73.7) | 133 (84.2) | 58 (78.4) | ||
| Maximum 2D diameter(mm, average ± SD) | 12.6 ± 5.7 | 15.1 ± 6.0 | <0.001 | 12.0 ± 5.2 | 15.4 ± 5.7 | <0.001 |
| Location | ||||||
| Left upper lobe | 86 (23.5) | 45 (26.3) | 0.497 | 44 (27.8) | 23 (31.1) | 0.726 |
| Left lower lobe | 53 (14.5) | 28 (16.4) | 28 (17.7) | 10 (13.5) | ||
| Right upper lobe | 136 (37.2) | 62 (36.3) | 58 (36.7) | 28 (37.8) | ||
| Right middle lobe | 17 (4.6) | 11 (6.4) | 6 (3.8) | 5 (6.8) | ||
| Right lower lobe | 74 (20.2) | 25 (14.6) | 22 (13.9) | 8 (10.8) | ||
Note: Ki‐67 (−) indicates low Ki‐67 LI and Ki‐67 (+) indicates high Ki‐67 LI.