Table 3 Comparison of noncontrast computed tomography features among absorbable benign, nonabsorbable benign, and malignant subsolid nodules

Location

0.949 ^a

0.214 ^a

0.244 ^a

 Upper lobe

44 (63.77%)

45 (64.29%)

212 (71.38%)

 Middle/lower lobe

25 (36.23%)

25 (35.71%)

85 (28.62%)

Size (mm)

0.123 ^b

0.019 ^b

 < 0.001 ^b

 Average

10.00 ± 6.00

9.00 ± 5.00

11.00 ± 4.00

 Range

5–23

5–21

8–27

Margin

 < 0.001 ^a

 < 0.001 ^a

0.661 ^a

 Well-defined

9 (13.04%)

39 (55.71%)

174 (58.59%)

 Ill-defined

60 (86.96%)

31 (44.29%)

123 (41.41%)

Shape

0.556 ^a

 < 0.001 ^a

 < 0.001^a

 Regular

39 (56.52%)

43 (61.43%)

243 (81.82%)

 Irregular

30 (43.48%)

27 (38.57%)

54 (18.18%)

Density

0.554 ^a

0.566 ^a

0.183 ^a

 GGO

34 (49.28%)

38 (54.29%)

135 (45.45%)

 PSO

35 (50.72%)

32 (45.71%)

162 (54.55%)

CT value of GGO areas (HU)

 − 633.04 ± 117.31

 − 635.53 ± 112.98

 − 592.00 ± 167.00

0.899 ^c

0.001 ^b

 < 0.001^b

Target sign

12 (17.39%)

9 (12.86%)

11 (3.70%)

0.455 ^a

 < 0.001 ^a

0.006 ^a

Air bronchogram

4 (5.80%)

4 (5.71%)

33 (11.11%)

1.000 ^a

0.187 ^a

0.177 ^a

Bubble lucency

0 (0%)

2 (2.86%)

44 (14.81%)

0.496 ^a

0.001 ^a

0.007 ^a

Abnormal intranodular vessel sign

7 (10.14%)

9 (12.86%)

46 (15.49%)

0.616 ^a

0.256 ^a

0.579 ^a

Thickened interlobular septa

6 (8.70%)

1 (1.43%)

3 (1.01%)

0.116 ^a

0.001 ^a

0.573 ^a

Satellite lesions

9 (13.04%)

4 (5.71%)

11 (3.70%)

0.138 ^a

0.005 ^a

0.668 ^a

Pleural retraction

2 (2.90%)

7 (10.00%)

48 (16.16%)

0.175 ^a

0.004 ^a

0.194 ^a

Pleural attachment

13 (18.84%)

13 (18.57%)

65 (21.89%)

0.968 ^a

0.578 ^a

0.542 ^a