Predictive CT findings of malignancy in ground-glass nodules on thin-section chest CT: the effects on radiologist performance

Abstract

Our purpose was to identify thin-section chest computed tomography (CT) findings of malignancy other than the presence of a solid portion within ground-glass nodules (GGNs) and to evaluate whether the radiologists' performance in determining malignancy can be enhanced with this information. The predictive CT findings of malignancy extracted from the CT findings of 80 GGNs (47 malignant, 33 benign) were a size of >8 mm [odds ratio (OR), 10.930; P = 0.045] and a lobulated border (OR, 13.769; P = 0.016) for pure GGNs and a lobulated border (OR, 10.200; P = 0.024) for mixed GGNs. Four chest radiologists and five radiology residents participated in the observer performance study with CT of 130 GGNs (67 malignant, 63 benign). Receiver-operating characteristic (ROC) analysis was used to compare radiologists' performances before and after providing these predictive findings. For pure GGNs, mean areas under the curve (A(z)) of all readers without and with CT predictive information were significantly different (0.621 +/- 0.052 and 0.766 +/- 0.055, P < 0.05). For mixed GGNs, the A(z) values achieved without and with predictive information were not significantly different (0.727 +/- 0.064 and 0.764 +/- 0.056, P > 0.05). Information about lesion size and morphological characteristics can enhance radiologists' performance in determining malignancy of pure GGNs.

Analysis of pulmonary pure ground-glass nodule in enhanced dual energy CT imaging for predicting invasive adenocarcinoma: comparing with conventional thin-section CT imaging

“…This might be related to the possibly similar vessels distribution between different histological subtypes of adenocarcinoma, and further investigation about quantifying microvessel densities which may help to explain it is needed. Similar to the former studies (5,10,12), the nonenhanced CT number of IA was higher than that of AIS or MIA, but the difference was not obvious in our study, and this result did not concur with the former researches (5,10,12). The possible reason could be the small number of cases of IA, however, enhanced monochromatic CT number of 120-140 keV which was less influenced by iodine, performed better than nonenhanced CT number to indicate IA.…”

“…Most pGGNs tend to be preinvasive (1), while approximately 20-40% of pGGNs are pathologically malignant (10). Because of the limited resolution (0.2-0.3 mm) of CT images, stromal or myofibroblastic invasion of 5 mm or smaller in MIA or even IA greater than 5 mm in size may manifest as pGGN on high resolution CT (5).…”

Incidental, subsolid pulmonary nodules at CT: etiology and management

“…10 and 11) [6] . Although PET/CT is a valuable tool for staging NSCLC by improving detection of local and distant metastases, its use in staging cancers manifesting as pure GGNs is limited because of the very low probability of nodal and distant metastases associated with these lesions [7] . PSNs with 450% ground-glass component are also unlikely to show nodal or distant metastases [7] .…”

The Self-Overlap Method for Assessment of Lung Nodule Morphology in Chest CT

“…Irregular borders have been associated with malignancy in solid nodules. For subsolid nodules, including part solid and pure ground glass lesions, margin features have not been proven significant as of yet in differentiating benign from malignant counterparts [11], although future investigation may elucidate any predictive nature [12]. Therefore, the focus of this investigation will be on solid nodules.…”