title: Performance of Lung-RADS in the National Lung Screening Trial: a retrospective assessment.
abstract: BACKGROUND
  Lung cancer screening with low-dose computed tomography (LDCT) has been recommended, based primarily on the results of the NLST (National Lung Screening Trial). The American College of Radiology recently released Lung-RADS, a classification system for LDCT lung cancer screening.
  
  
  OBJECTIVE
  To retrospectively apply the Lung-RADS criteria to the NLST.
  
  
  METHODS
  Secondary analysis of a group from a randomized trial.
  
  
  METHODS
  33 U.S. screening centers.
  
  
  METHODS
  Participants were randomly assigned to the LDCT group of the NLST, were aged 55 to 74 years, had at least a 30-pack-year history of smoking, and were current smokers or had quit within the past 15 years.
  
  
  METHODS
  3 annual LDCT lung cancer screenings.
  
  
  METHODS
  Lung-RADS classifications for LDCT screenings. Lung-RADS categories 1 to 2 constitute negative screening results, and categories 3 to 4 constitute positive results.
  
  
  RESULTS
  Of 26 722 LDCT group participants, 26 455 received a baseline screening; 48 671 screenings were done after baseline. At baseline, the false-positive result rate (1 minus the specificity rate) for Lung-RADS was 12.8% (95% CI, 12.4% to 13.2%) versus 26.6% (CI, 26.1% to 27.1%) for the NLST; after baseline, the false-positive result rate was 5.3% (CI, 5.1% to 5.5%) for Lung-RADS versus 21.8% (CI, 21.4% to 22.2%) for the NLST. Baseline sensitivity was 84.9% (CI, 80.8% to 89.0%) for Lung-RADS versus 93.5% (CI, 90.7% to 96.3%) for the NLST, and sensitivity after baseline was 78.6% (CI, 74.6% to 82.6%) for Lung-RADS versus 93.8% (CI, 91.4% to 96.1%) for the NLST.
  
  
  CONCLUSIONS
  Lung-RADS criteria were applied retrospectively.
  
  
  CONCLUSIONS
  Lung-RADS may substantially reduce the false-positive result rate; however, sensitivity is also decreased. The effect of using Lung-RADS criteria in clinical practice must be carefully studied.
  
  
  BACKGROUND
  National Institutes of Health.
authors: Paul F
authors: PF
authors: Pinsky
authors: David S
authors: DS
authors: Gierada
authors: William
authors: W
authors: Black
authors: Reginald
authors: R
authors: Munden
authors: Hrudaya
authors: H
authors: Nath
authors: Denise
authors: D
authors: Aberle
authors: Ella
authors: E
authors: Kazerooni
mesh_terms: D000368:Aged; D055088:Early Detection of Cancer / Q000379:methods*; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging*; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D011237:Predictive Value of Tests; D011829:Radiation Dosage; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*