Window Settings in the Diagnosis of Invasiveness of Lung Adenocarcinoma with Ground Glass Opacities / 中国医学影像学杂志

ABSTRACT

Purpose To explore the value of window width adjustment in diagnosing the invasiveness of lung adenocarcinoma manifested as ground glass opacities on high-resolution CT, and to provide guidance for the diagnosis of lung adenocarcinoma in different types. Materials and Methods The preoperative CT data of 102 preinvasive lesions and 107 invasive lesions of lung adenocarcinoma were analyzed retrospectively. Among 102 cases of preinvasive lesions, 25 were atypical adenomatous hyperplasia (AAH), 77 were adenocarcinoma in situ (AIS). Among 107 cases of invasive lesions, 78 were minimally invasive adenocarcinoma (MIA), and 29 were invasive adenocarcinoma. The lesions were ground glass opacity (GGO) on lung window while were invisible on mediastinal window. The window width was adjusted constantly until the lesions were invisible with the fixed mediastinal window level (40 HU). When the lesions became invisible, the window width was compared and the best cut-off was found on ROC curve in the two groups. Results The window width of lesions between preinvasive lesions and invasive lesions was different (Z= - 6.203, P<0.05). Window width was a good indicator for the invasiveness of pulmonary adenocarcinoma (area under the ROC was 0.748, P<0.05), and the window width of 1303 HU was the best cut-off for preinvasive lesions and invasive lesions (sensitivity was 56.9%, specificity was 86.0%. Conclusion Window width may be useful for the diagnosis of the invasiveness of the GGO of lung adenocarcinoma on HRCT. The lesion disappearing when the window width is larger than 1303 HU is more likely to be preinvasive; while the lesion disappearing when the window width is smaller than 1303 HU is more likely to be an invasive one.