title: Pulmonary nodules: volume repeatability at multidetector CT lung cancer screening.
abstract: OBJECTIVE
  To assess in vivo volumetric repeatability of an automated software algorithm in pulmonary nodules detected during a lung cancer screening trial.
  
  
  METHODS
  This study was approved by an institutional review board. Written informed consent was obtained from all participants. Data were collected from the Multicentric Italian Lung Detection project, a randomized controlled lung cancer screening trial. The first 1236 consecutive baseline computed tomographic (CT) studies performed at the Istituto Nazionale Tumori of Milan were evaluated. Among the enrolled participants, those who underwent repeat low-dose CT after 3 months and had at least one indeterminate nodule with a volume of more than 60 mm(3) (diameter of 4.8 mm or greater) were considered. Nonsolid, part-solid, and pleural-based nodules were excluded from this study. A descriptive analysis was performed by calculating means and standard deviations of nodule volumes at three assessment times (at baseline and 3 and 12 months later). The volume measurement repeatability was determined by using the approach described by Bland and Altman.
  
  
  RESULTS
  One hundred one subjects (70 men, 31 women; mean age, 58 years) with 233 eligible nodules (mean volume, 98.3 mm(3); range, 5-869 mm(3)) were identified. The 95% confidence interval for difference in measured volumes was in the range of +/-27%. About 70% of measurements had a relative difference in nodule volume of less than 10%. No malignant lesions were registered during the follow-up of these subjects.
  
  
  CONCLUSIONS
  Semiautomatic volumetry is sufficiently accurate and repeatable and may be useful in assisting with lung nodule management in a lung cancer screening program.
authors.affiliation: Department of Diagnostic Imaging and Radiotherapy, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian 1, 20133 Milan, Italy. alfonso.marchiano@istitutotumori.mi.it
authors.forename: Alfonso
authors.initials: A
authors.lastname: Marchianò
authors.forename: Elisa
authors.initials: E
authors.lastname: Calabrò
authors.forename: Enrico
authors.initials: E
authors.lastname: Civelli
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Di Tolla
authors.forename: Laura Francesca
authors.initials: LF
authors.lastname: Frigerio
authors.forename: Carlo
authors.initials: C
authors.lastname: Morosi
authors.forename: Francesco
authors.initials: F
authors.lastname: Tafaro
authors.forename: Elena
authors.initials: E
authors.lastname: Ferri
authors.forename: Nicola
authors.initials: N
authors.lastname: Sverzellati
authors.forename: Tiziana
authors.initials: T
authors.lastname: Camerini
authors.forename: Luigi
authors.initials: L
authors.lastname: Mariani
authors.forename: Salvatore
authors.initials: S
authors.lastname: Lo Vullo
authors.forename: Ugo
authors.initials: U
authors.lastname: Pastorino
mesh_terms: D000368:Aged; D000465:Algorithms; D000704:Analysis of Variance; D005260:Female; D006801:Humans; D007558:Italy; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D003074:Solitary Pulmonary Nodule / Q000000981:diagnostic imaging* / Q000473:pathology; D014057:Tomography, X-Ray Computed / Q000379:methods*