Fig. 2

a-d CT and pathological images of one adenocarcinoma in situ (AIS) appearing as subsolid nodule (SSN). a CT multiplanar reconstruction (MPR) and b volume rending technique (VRT) showing the absence of vascular change, and lobulation (axial and coronal). c The long axis, short axis, and mean CT value were calculated using the semi-automated segmentation tool. d Pathology: the tumor cells were attached to the alveolar wall; the basement membrane was intact. (HE staining ×100). e-h CT and pathological images of one invasive adenocarcinoma (IAC) appearing as SSN. e CT MPR and f maximal intensity projection (MIP) showing the presence of vascular change, and lobulation (axial and sagittal). g The long axis, short axis, and mean CT value were calculated using the semi-automated segmentation tool. h Pathology: the tumor cells damaged alveolar cells, a large number of tumor cells infiltrating the interstitium. (HE staining ×100)