title: Radiology review of the UKCCCR Breast Screening Frequency Trial: potential improvements in sensitivity and lead time of radiological signs.
abstract: OBJECTIVE
  To review all previous mammograms of breast cancer cases diagnosed during a randomized trial comparing 3 yearly to annual mammographic screening with a view to identifying and quantifying cases that might potentially have been diagnosed earlier.
  
  
  METHODS
  Mammograms of 602 breast cancer cases (399 screen-detected and 203 interval cases) were reviewed in chronological order and suspicious radiological features noted for each mammogram, up to and including the diagnostic mammogram.
  
  
  RESULTS
  Of the 602 cases, 79 (13%) had features at diagnosis that were visible on previous mammograms, suggesting a sensitivity of interpretation of 87%. A similar proportion of screen-detected (14%) and interval cancers (11%) had signs at diagnosis that were visible on previous mammograms. The potential for improvement was particularly noted for asymmetric density (sensitivity = 77%, average time visible before diagnosis 14 months) and parenchymal deformity/stellate lesion (sensitivity = 81%, average time visible before diagnosis 12 months).
  
  
  CONCLUSIONS
  The highest sensitivity was observed for comedo-type microcalcifications (sensitivity = 97%, average time visible before diagnosis 5 months). By improvements in sensitivity to asymmetric density and parenchymal deformity/stellate lesion, 4% of tumours could have their time of diagnosis advanced substantially.
authors.affiliation: Department of Radiology, St Margaret's Hospital, Epping, UK. rmlw2@cam.ac.uk
authors.forename: R M L
authors.initials: RM
authors.lastname: Warren
authors.forename: J R
authors.initials: JR
authors.lastname: Young
authors.forename: L
authors.initials: L
authors.lastname: McLean
authors.forename: K
authors.initials: K
authors.lastname: Lyons
authors.forename: A R M
authors.initials: AR
authors.lastname: Wilson
authors.forename: A
authors.initials: A
authors.lastname: Evans
authors.forename: S W
authors.initials: SW
authors.lastname: Duffy
authors.forename: I M
authors.initials: IM
authors.lastname: Warsi
mesh_terms: D000328:Adult; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D002114:Calcinosis / Q000000981:diagnostic imaging; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000000981:diagnostic imaging; D003951:Diagnostic Errors; D004739:England; D005188:False Negative Reactions; D005260:Female; D006801:Humans; D008327:Mammography / Q000592:standards*; D008403:Mass Screening / Q000379:methods / Q000592:standards*; D008485:Medical Audit; D009361:Neoplasm Invasiveness; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014852:Wales