Correlation between histological invasiveness and the computed tomography value in pure ground-glass nodules

Abstract

PurposeThe purpose of this study was to evaluate the correlation between histological invasiveness and the computed tomography (CT) value and size in pure ground-glass nodules (GGNs) to determine optimal “follow-up or resection” strategies.MethodsBetween 2001 and 2014, 78 resected, pure GGNs were retrospectively evaluated. The maximum diameter and CT value of pure GGNs were measured using a computer graphics support system.ResultsAll GGNs with a maximum diameter ≤10 mm and CT value ≤−600 Hounsfield units (HU) were considered to be noninvasive lesions, while 21 of 26 (81 %) with a maximum diameter >10 mm and CT value >−600 HU were considered to be invasive lesions. With respect to the correlation between each histological type and pure GGN with a maximum diameter ≤10 mm and CT value ≤−600 HU, the specificity was 90 % and the sensitivity and negative predictive value were both 100 % in atypical adenomatous hyperplasia (AAH), while the specificity was 58 % and the sensitivity and positive predictive value were 0 % in minimally invasive and invasive adenocarcinoma.ConclusionPure GGNs with a maximum diameter of ≤10 mm and CT value of ≤−600 HU are nearly always pre-invasive lesions; therefore, surgery should be carefully selected in such patients.

Factors distinguishing invasive from pre-invasive adenocarcinoma presenting as pure ground glass pulmonary nodules

“…Because integers are more convenient in clinical practice, we used published cutoff values in our univariable and multivariable analyses (age > 55 years, maximal diameter > 1 cm, CT density > −600 HU). In the present study, model 2 suggested that maximal and mean diameters could reliably and independently distinguish IACs in patients with pGGNs with diameters of < 3 cm; this nding was consistent with reported literature [11,15].In the current study, a tumor diameter of > 10 mm was a signi cant independent predictor of IAC; however, that result is not readily apparent from the scatter plot shown in Figure 3. The best predictor of IAC may be a diameter of > 20 mm, because only one of the pre-IACs shown in Figure 3 had a diameter > 20 mm.…”

“…Several studies have analyzed relationships between CT features of pGGNs and pathological type [15][16][17][18]. However, to the best of our knowledge, no published study has identi ed predictors of lung IACs in pGGNs by analyzing their clinical and imaging characteristics.…”

“…However, to the best of our knowledge, no published study has identi ed predictors of lung IACs in pGGNs by analyzing their clinical and imaging characteristics. The present study investigated 659 adenocarcinomas manifesting as pGGNs on CT; thus, making the study was larger than most recent studies regarding pathological classi cation of pGGNs [11,15,17,[19][20].…”

“…Kitami et al [15] reported cutoffs of −600 HU for CT density and 10 mm for maximum diameter for distinguishing between IAC and non-IAC pGGNs of the lung. The corresponding cutoffs identi ed in the current study are similar to those values, and other previously reported values [11].…”

Adenocarcinoma in pure ground glass nodules: histological evidence of invasion and open debate on optimal management

“…They addressed the CT characterization of resected pGGN adenocarcinoma in the three categories of stromal infiltration: adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), and invasive adenocarcinoma (IAC) (3). This is one of the few reports in non-Asian population (only 10% of patients were Asian), compared to a majority of Asian studies related to the quite common surgical approach to pGGN ( Table 1) (4)(5)(6)(7)(8)(9)(10)(11)(12). Notably, the reported results detail the CT appearance through the continuum of adenocarcinoma invasiveness and show the direct association between radiological size of pGGN and conspicuity of stromal invasion on histological specimen (e.g., number and size of invasive foci).…”