title: Longitudinal evolution of incidentally detected solitary pure ground-glass nodules on CT: relation to clinical metrics.
abstract: OBJECTIVE
  We aimed to assess the relation between basic clinical parameters and evolution of solitary pure ground-glass nodules (pGGN) in the lungs.
  
  
  METHODS
  Baseline and follow-up computed tomography (CT) of patients with solitary pGGN were selected and two radiologists independently reviewed CTs for nodule characterization. CT features of solitary pGGN were manually measured maximum diameter (D1) and its orthogonal diameter (D2), mean diameter (mD), D1 to D2 ratio as surrogate of roundness, and location according to lobar anatomy. Longitudinal changes were assessed and solitary pGGNs were classified as resolved or persisting. Persisting nodules were further classified as stable or grown according to an increase in mD of ≥2 mm or appearance of solid component. Baseline CT features of solitary pGGNs and clinical metrics of patients were compared between resolved and persisting nodules and, thereafter, between stable and grown lesions.
  
  
  RESULTS
  A total of 95 subjects with solitary pGGN were included. After a median 16-month follow-up, 20 nodules resolved, while 75 persisted. Among persisting nodules, 18 were grown and 57 were stable. Grown nodules showed larger D1 and mD compared with stable pGGNs (P < 0.001). Subjects with grown nodules were older (P = 0.021). Logistic regression analyses showed higher likelihood of growth for nodules ≥10 mm (odds ratio [OR], 8.355; P = 0.001) and subjects older than 67 years (OR, 3.656; P = 0.034).
  
  
  CONCLUSIONS
  Nodules ≥10 mm in subjects older than 67 years showed higher likelihood of growth. These data could contribute to a more individual approach to the management of solitary pGGN.
authors.affiliation: Section of Radiology, Department of Surgery, University Hospital of Parma, Italy; Section of Cardiothoracic Imaging, Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA. mariosilvamed@gmail.com.
authors.forename: Mario
authors.initials: M
authors.lastname: Silva
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Bankier
authors.forename: Francesco
authors.initials: F
authors.lastname: Centra
authors.forename: Davide
authors.initials: D
authors.lastname: Colombi
authors.forename: Luca
authors.initials: L
authors.lastname: Ampollini
authors.forename: Paolo
authors.initials: P
authors.lastname: Carbognani
authors.forename: Nicola
authors.initials: N
authors.lastname: Sverzellati
mesh_terms: D000367:Age Factors; D000368:Aged; D018450:Disease Progression; D005260:Female; D006801:Humans; D033162:Incidental Findings; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D003074:Solitary Pulmonary Nodule / Q000000981:diagnostic imaging* / Q000473:pathology*; D014057:Tomography, X-Ray Computed / Q000379:methods*