Table 2.

Imaging features of GGNs classified into different histologic types

Characteristics	AIS (n=12)	MIA (n=14)	IA (n=55)	P-value
Size (mean ± standard deviation, cm)	1.45±0.60	1.49±0.55	2.00±0.87	0.016*
Density (n)				<0.001*
pGGNs	10	9	16
mGGNs	2	5	39
Shape (n)				0.027**
Round	8	6	15
Oval	1	2	4
Irregular	3	6	36
Margin (n)				0.190
Smooth	10	10	28
Lobular	1	2	8
Spiculated	1	0	14
Lobular and spiculated	0	2	5
Pleural tag (n)	1	2	26	0.007*
Vascular cluster (n)	0	2	13	0.146
Bubble-like sign (n)	3	5	23	0.542
Air bronchogram (n)	1	3	13	0.498

Notes:

^*IA vs AIS and MIA statistically significant;

^**IA vs AIS statistically significant.

Abbreviations: GGN, ground-glass opacity nodule; AIS, adenocarcinoma in situ; MIA, minimally invasive adenocarcinoma; IA, invasive pulmonary adenocarcinoma; pGGN, pure ground-glass opacity nodule; mGGN, mixed ground-glass opacity nodule.