Differentiating Preinvasive from Invasive Lung Adenocarcinoma Appearing as Part-Solid Ground-Glass Nodule Using CT Value and Solid-Part Diameter

Abstract

Objectives: To evaluate the differentiating roles of computed tomography (CT) for invasive adenocarcinomas (IACs) of the lung from preinvasive lesions or minimally invasive adenocarcinomas (MIAs) manifesting as part-solid ground-glass nodules (GGNs). Patients and Methods: All 230 lesions were pathologically confirmed. Their size, CT parameters and morphological features were compared among the three groups. Optimal cut-off values were calculated for parameters with diagnostic value. Results: The diameter of the GGN lesion and the maximum diameter of the solid part, as well as CT values of the ground-glass part and the solid part differed significantly among the three groups. Cut-off maximum diameter of the solid part was 2.5 and 5.5 mm to differentiate preinvasive vs. MIA and MIA vs. IAC, respectively. Cut-off mean CT value was -581 and -464 hounsfield unit (HU) to differentiate preinvasive vs. MIA and MIA vs. IAC, respectively. Cut-off CT value of the ground-glass part was -675 and -562 HU to differentiate the same three groups. Morphological characteristics such as lobulation, spiculation and air bronchograms were all more likely to occur in invasive lesions. Conclusion:The mean CT value, CT value of the ground glass part and maximum solid-part diameter of a GGN can help differentiate preinvasive from invasive lung adenocarcinomas.

Control Study between CT Signs and Pathological Subtypes and Differentiation Degree in Lung Adenocarcinoma

“…According to a study by Oda et al [15] , the occurrence rate of spicule sign in IAC was higher than that in PIL, the difference was statistically signi cant. Wang et al [16] reported that the incidence of pleural traction sign, lobulation sign, bronchial cut-off sign, air bronchogram sign and spicule sign in IAC was signi cantly higher than that in MIA and PIL, while there was no signi cant difference in cavity sign among the three groups. In our research there was no signi cant difference in the distribution of vacuole sign in PIL, MIA and IAC, but the incidence of cavity sign in IAC was higher than that in the other two groups, and the difference was statistically signi cant(P<0.01).…”