title: Pulmonary ground-glass nodules diagnosis: mean change rate of peak CT number as a discriminative factor of pathology during a follow-up.
abstract: OBJECTIVE
  We aimed to analyse the peak CT number (PEAK) in CT number histogram of ground-glass nodules (GGN), meaning the most frequent density of pixels in the image of pulmonary nodule, based on three-dimensional (3D) reconstructive model pre-operatively, and the mean rate of PEAK change (V-PEAK) during a follow-up of GGN for differential diagnosis between pre-invasive adenocarcinoma (PIA) and invasive adenocarcinoma (IAC).
  
  
  METHODS
  CT number histogram of pixels in GGN was made automatically by 3D measurement software. Diameter, total volume, PEAK and V-PEAK were measured from CT data sets of different groups classified by pathology, subtype and number of GGN, respectively.
  
  
  RESULTS
  Among all 102 cases, 47 were PIA, including atypical adenomatous hyperplasia (n = 29) and adenocarcinoma in situ (n = 18), and 55 were IAC, including minimally IAC (MIA, n = 4). By Wilcoxon test, PEAK of IAC was significantly higher than that of PIA (p < 0.001). By receiver operating curve analysis, area under the curve (AUC) was 0.857 and threshold -820.50 Hounsfield units (HU) for differentiation between PIA and IAC. V-PEAK of IAC was unexpectedly remarkably smaller than that of PIA (p < 0.001) with AUC and threshold being 0.810 and -0.829 HU day(-1), respectively.
  
  
  CONCLUSIONS
  Pre-operative PEAK and V-PEAK, which interpret and evaluate the change of volume and density of pulmonary nodule simultaneously from both exterior and interior perspectives, can help to distinguish IAC from PIA.
  
  
  CONCLUSIONS
  This study provided researchers of GGN another perspective, taking both volume and density of nodules into consideration for pathological evaluation.
authors.affiliation: 1 Department of Thoracic Surgery, Shanghai First People's Hospital Affiliated to The Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Mingzheng
authors.initials: M
authors.lastname: Peng
authors.affiliation: 1 Department of Thoracic Surgery, Shanghai First People's Hospital Affiliated to The Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Li
authors.affiliation: 1 Department of Thoracic Surgery, Shanghai First People's Hospital Affiliated to The Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Haiyang
authors.initials: H
authors.lastname: Hu
authors.affiliation: 1 Department of Thoracic Surgery, Shanghai First People's Hospital Affiliated to The Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Sida
authors.initials: S
authors.lastname: Liu
authors.affiliation: 1 Department of Thoracic Surgery, Shanghai First People's Hospital Affiliated to The Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Binbin
authors.initials: B
authors.lastname: Xu
authors.affiliation: 1 Department of Thoracic Surgery, Shanghai First People's Hospital Affiliated to The Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Wenzhuo
authors.initials: W
authors.lastname: Zhu
authors.affiliation: 1 Department of Thoracic Surgery, Shanghai First People's Hospital Affiliated to The Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Yudong
authors.initials: Y
authors.lastname: Han
authors.affiliation: 2 Department of Respiration, Shanghai Chest Hospital Affiliated to The Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Liwen
authors.initials: L
authors.lastname: Xiong
authors.affiliation: 1 Department of Thoracic Surgery, Shanghai First People's Hospital Affiliated to The Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Lin
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D055613:Multiple Pulmonary Nodules / Q000000981:diagnostic imaging* / Q000473:pathology; D011230:Precancerous Conditions / Q000000981:diagnostic imaging* / Q000473:pathology; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*