title: [Three Dimensional Volumetric Analysis of Solid Pulmonary Nodules on Chest CT:  Cancer Risk Assessment].
abstract: BACKGROUND
  The management of pulmonary nodules relies on cancer risk assessment, in which the only widely accepted criterion is diameter. The development of volumetric computed tomography (CT) and three-dimensional (3D) software enhances the clarity in displaying the nodules' characteristics. This study evaluated the values of the nodules' volume and 3D morphological characteristics (edge, shape and location) in cancer risk assessment.
  
  
  METHODS
  The CT data of 200 pulmonary nodules were retrospectively evaluated using 3D volumetric software. The malignancy or benignity of all the nodules was confirmed by pathology, histology or follow up (>2 years). Logistic regression analysis was performed to calculate the odds ratios (ORs) of the 3D margin (smooth, lobulated or spiculated/irregular), shape (spherical or non-spherical), location (purely intraparenchymal, juxtavascular or pleural-attached), and nodule volume in cancer risk assessment for total and sub-centimeter nodules. The receiver operating characteristic (ROC) curve was employed to determine the optimal threshold for the nodule volume.
  
  
  RESULTS
  Out of 200 pulmonary nodules, 78 were malignant, whereas 122 were benign. The Logistic regression analysis showed that the volume (OR=3.3; P<0.001) and the 3D margin (OR=13.4, 9.8; both P=0.001) were independent predictive factors of malignancy, whereas the location and 3D shape exhibited no total predictive value (P>0.05). ROC analysis showed that the optimal threshold for malignancy was 666 mm³. For sub-centimeter nodules, the 3D margin was the only valuable predictive factor of malignancy (OR=60.5, 75.0; P=0.003, 0.007).
  
  
  CONCLUSIONS
  The volume and 3D margin are important factors considered to assess the cancer risk of pulmonary nodules. Volumes larger than 666 mm³ can be determined as high risk for pulmonary nodules; by contrast, nodules with lobulated, spiculated, or irregular margin present a high malignancy probability.
authors.affiliation: Department of Radiology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Mengqi
authors.initials: M
authors.lastname: Li
authors.affiliation: Department of Radiology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Rongcheng
authors.initials: R
authors.lastname: Han
authors.affiliation: Department of Pathology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Wenjing
authors.initials: W
authors.lastname: Song
authors.affiliation: Department of Radiology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Xinyue
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Radiology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Fangfang
authors.initials: F
authors.lastname: Guo
authors.affiliation: Department of Radiology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Datong
authors.initials: D
authors.lastname: Su
authors.affiliation: Department of Radiology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Tielian
authors.initials: T
authors.lastname: Yu
authors.affiliation: Department of Radiology, Tianjin Medical University General Hospital, Tianjin 300052, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000368:Aged; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000401:mortality; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D012189:Retrospective Studies; D018570:Risk Assessment; D003074:Solitary Pulmonary Nodule / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000401:mortality; D014057:Tomography, X-Ray Computed