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Abstract

We would like to thank to Drs Tamura and Satoh for their interest regarding our study on quantitative CT analysis of pure ground-glass opacity nodules to predict further CT change.1Bak S.H. Lee H.Y. Kim J.H. et al.Quantitative CT scanning analysis of pure ground-glass opacity nodules predicts further CT scanning change.Chest. 2016; 149: 180-191Abstract Full Text Full Text PDF PubMed Scopus (64) Google Scholar We are grateful for their questions, for which our responses are listed as follows. We included three histological types of adenocarcinoma in situ, minimally invasive adenocarcinoma, and invasive adenocarcinoma. Thus, ground-glass opacity nodules of interest to us were classified into three pathological types upon examination of the resected tumor, which is based on the International Association for the Study of Lung Cancer, American Thoracic Society, and European Respiratory Society international multidisciplinary classification system. In our study, tumors were divided into three subregions of former bronchioloalveolar carcinoma (BAC) component, non-BAC component, and central fibrosis component. Regarding their question about the definition of solid component, the solid component region (non-BAC region) was defined as the areas of the tumor; the tumor (1) contains an invasive component; (2) invades lymphatics, blood vessels, or pleura; or (3) contains tumor necrosis.2Lee H.Y. Choi Y.L. Lee K.S. et al.Pure ground-glass opacity neoplastic lung nodules: histopathology, imaging, and management.AJR Am J Roentgenol. 2014; 202: W224-W233Crossref PubMed Scopus (144) Google Scholar, 3Lee H.Y. Han J. Lee K.S. et al.Lung adenocarcinoma as a solitary pulmonary nodule: prognostic determinants of CT, PET, and histopathologic findings.Lung Cancer (Amsterdam, Netherlands). 2009; 66: 379-385Abstract Full Text Full Text PDF PubMed Scopus (48) Google Scholar In addition, the former BAC region was defined as the area of lepidic growth without invasion of stroma, blood vessels, or pleural. The concept of an adenocarcinoma sequence of the lung is that atypical adenomatous hyperplasia would progress to lepidic growth without central collapse or fibrotic regions and then to lepidic growth with central fibrotic foci.4Suzuki K. Yokose T. Yoshida J. et al.Prognostic significance of the size of central fibrosis in peripheral adenocarcinoma of the lung.Ann Thorac Surg. 2000; 69: 893-897Abstract Full Text Full Text PDF PubMed Scopus (230) Google Scholar The central fibrosis is defined as the areas of fibroblastic focus in which a moderate or abundant amount of collagen or hyalinized tissue is clearly noted.5Lee H.Y. Jeong J.Y. Lee K.S. et al.Solitary pulmonary nodular lung adenocarcinoma: correlation of histopathologic scoring and patient survival with imaging biomarkers.Radiology. 2012; 264: 884-893Crossref PubMed Scopus (46) Google Scholar Regarding the central fibrosis, fibrous areas were not located always exactly in the epicenter of the tumor; however, there was no case in which the fibrous area was located the periphery of the tumor at all. Central fibrosis is a term used in the customary pathology. As previously reported,3Lee H.Y. Han J. Lee K.S. et al.Lung adenocarcinoma as a solitary pulmonary nodule: prognostic determinants of CT, PET, and histopathologic findings.Lung Cancer (Amsterdam, Netherlands). 2009; 66: 379-385Abstract Full Text Full Text PDF PubMed Scopus (48) Google Scholar the position of central fibrosis was analyzed with sections that included the largest cut of tumor tissue. Quantitative CT Scanning Analysis of Pure Ground-Glass Opacity Nodules Predicts Further CT Scanning ChangeCHESTVol. 149Issue 1PreviewWe sought to determine whether quantitative analysis of lung adenocarcinoma manifesting as a ground-glass opacity (GGO) nodule (GGN) on initial CT scans can predict further CT scanning change or rate of growth. Full-Text PDF Quantitative CT Scanning Analysis of Pure Ground-Glass Opacity Nodules Predicts Further CT ChangeCHESTVol. 149Issue 6PreviewWe read with interest the article by Bak et al1 in CHEST (January 2016) on quantitative CT scanning analysis of pure ground-glass opacity nodules to predict further CT change. We would like to hear the authors’ comments regarding the following three points. First, why did the authors include three different histological tumor types in this study, namely adenocarcinoma in situ, minimally invasive adenocarcinoma, and invasive adenocarcinoma. Does this mean “ground-glass opacity nodules” were classified into these three pathological types upon examination of resected tumors? Second, although the authors provided a definition for a “central fibrotic lesion” in the Materials and Methods section, a lesion’s “solid component” was not defined anywhere in the article. Full-Text PDF