Table 1. Morphologic features and CT measurements of solitary GGNs with stage IA lung cancer on HRCT.
| Features | Type | AIS-MIA (n = 15) | IAC (n = 43) | p Value |
|---|---|---|---|---|
| Nodule Type | pure GGN | 8 (53.3) | 2 (4.7) | 0.000* |
| mixed GGN | 7 (46.7) | 41 (95.3) | ||
| Position | subpleural/perifissural | 12 (80.0) | 40 (83.0) | 0.350* |
| parenchymal | 3 (20.0) | 3 (7.0) | ||
| Shape | oval/round | 11 (73.3) | 26 (60.5) | 0.372* |
| irregular/polygonal | 4 (26.7) | 17 (39.5) | ||
| Margin | smooth | 7 (46.7) | 21 (48.8) | 0.885* |
| lobulated/spiculated | 8 (53.3) | 22 (51.2) | ||
| Bronchus sign | natural | 12 (80.0) | 25 (58.1) | 0.129* |
| dilated/distorted | 0 (0) | 6 (14.0) | 0.300* | |
| cut-off | 0 (0) | 1 (2.3) | 1.000** | |
| Cystic appearance | presence | 0 (0) | 12 (27.9) | 0.016* |
| Pleural indentation | presence | 6 (40.0) | 38 (88.4) | 0.054* |
| Vascular convergence | presence | 12 (80.0) | 37 (86.0) | 1.000* |
| Diameter of GGN (mm) | 12.6 ± 3.3 (8.4~20.3) | 20.0 ± 5.6 (10.5~29.8) | 0.000† | |
| Diameter of solid component (mm) | 2.3 ± 2.8 (0~8.5) | 11.5 ± 6.8 (0~24.3) | 0.000† | |
| Consolidation/tumor ratio (%) | 16.2 ± 19.3 (0~51.2) | 54.5 ± 26.3 (0~94.8) | 0.000‡ | |
| CT value of GGO component (HU) | −562.4 ± 120.0(−835.2~–327.3) | −501.9 ± 115.1(−733.0~-314.3) | 0.089‡ | |
| ΔCTGGO-LP (HU) | 312.1 ± 132.5 (23.5~595.7) | 370.0 ± 109.2 (171.6~575.9) | 0.100‡ |
Note.— Data of morphologic features are expressed as number of cases with the percentages in parentheses. Data of CT measurements are expressed as mean ± standard deviation with the ranges in parentheses. GGN: ground-glass opacity nodule; HRCT: high-resolution computed tomography; AIS: adenocarcinoma in situ; MIA: minimally invasive adenocarcinoma; IAC: invasive adenocarcinoma; ΔCTGGO-LP: difference of CT value between GGO component and adjacent lung.
*Chi-square test; **Fisher`s Exact test; †Mann-Whitney U test; ‡Student t test.