Table 1 Baseline patient characteristics by diagnostic category
Variable | Total (n = 659) | Pre-IAC (n = 523) | IAC (n = 136) | χ2 | p |
|---|---|---|---|---|---|
Sex | 5.042 | 0.025 | |||
Male | 200 (30.3%) | 148 (28.3%) | 52 (38.2%) | ||
Female | 459 (69.7%) | 375 (71.7%) | 84 (61.8%) | ||
Age, years | 40.540 | < 0.001 | |||
≤ 55 | 325 (49.3%) | 291 (55.6%) | 34 (25.0%) | ||
> 55 | 334 (50.7%) | 232 (44.4%) | 102 (75.0%) | ||
Smoking history | 4.985 | 0.723 | |||
Never | 350 (53.1%) | 283 (54.1%) | 67 (49.3%) | ||
Current or former | 309 (46.9%) | 240 (45.9%) | 69 (50.7%) | ||
Symptoms | 5.742 | 0.831 | |||
Absent | 480 (72.8%) | 410 (78.4%) | 70 (51.5%) | ||
Present | 179 (27.2%) | 113 (21.6%) | 66 (48.5%) | ||
Serum CEA, μg/L | .069 | 0.792 | |||
< 5 | 652 (99.1%) | 518 (99.2%) | 134 (98.5%) | ||
≥ 5 | 6 (0.9%) | 4 (0.8%) | 2 (1.5%) | ||
Maximal diameter, cm | 145.831 | < 0.001 | |||
≤ 1 | 430 (65.2%) | 401 (76.7%) | 29 (21.3%) | ||
> 1 | 229 (34.8%) | 122 (23.3%) | 107 (78.7%) | ||
Mean diameter, cm | 188.727 | < 0.001 | |||
≤ 1 | 475 (72.0%) | 441 (84.3%) | 34 (25.0%) | ||
> 1 | 184 (28.0%) | 82 (15.7%) | 102 (75.0%) | ||
CT density, HU | 21.374 | < 0.001 | |||
≤ −600 | 344 (52.2%) | 297 (56.8%) | 47 (34.6%) | ||
> −600 | 315 (47.8%) | 226 (43.2%) | 89 (65.4%) | ||
Pleural retraction | 0.033 | 0.857 | |||
Absent | 633 (96.1%) | 502 (96.0%) | 131 (96.3%) | ||
Present | 26 (3.9%) | 21 (4.0%) | 5 (3.7%) | ||
Air bronchogram sign | .000 | 1.00 | |||
Absent | 647 (98.2%) | 513 (98.1%) | 134 (98.5%) | ||
Present | 12 (1.8%) | 10 (1.9%) | 2 (1.5%) | ||
Bubble lucency sign | 0.278 | 0.598 | |||
Absent | 598 (90.7%) | 473 (90.4%) | 125 (91.9%) | ||
Present | 61 (9.3%) | 50 (9.6%) | 11 (8.1%) | ||
Spiculated sign | 5.329 | 0.021 | |||
Absent | 560 (85.0%) | 453 (86.6%) | 107 (78.7%) | ||
Present | 99 (15.0%) | 70 (13.4%) | 29 (21.3%) |