title: Differences in radiological patterns, tumour characteristics and diagnostic precision between digital mammography and screen-film mammography in four breast cancer screening programmes in Spain.
abstract: OBJECTIVE
  To compare tumour characteristics between cancers detected with screen-film mammography (SFM) and digital mammography (DM) and to evaluate changes in positive predictive values (PPVs) for further assessments, for invasive procedures and for distinct radiological patterns in recalled women.
  
  
  METHODS
  242,838 screening mammograms (171,191 SFM and 71,647 DM) from 103,613 women aged 45-69 years, performed in four population-based breast cancer screening programmes in Spain, were included. The tumour characteristics and PPVs of each group were compared. Radiological patterns (masses, calcifications, distortions and asymmetries) among recalled women were described and PPVs were evaluated.
  
  
  RESULTS
  The percentages of ductal carcinoma in situ (DCIS) were higher in DM than in SFM both in the first [18.5% vs. 15.8%(p = 0.580)] and in successive screenings [23.2% vs. 15.7%(p = 0.115)]. PPVs for masses, asymmetries and calcifications were higher in DM, being statistically significant in masses (5.3% vs. 3.9%; proportion ratio: 1.37 95%CI: 1.08-1.72). Among cancers detected by calcifications, the percentage of DCIS was higher in DM (60.3% vs. 46.4%, p = 0.060).
  
  
  CONCLUSIONS
  PPVs were higher when DM was used, both for further assessments and for invasive procedures, with similar cancer detection rates and no statistically significant differences in tumour characteristics. The greatest improvements in PPVs were found for masses.
authors.affiliation: Department of Epidemiology and Evaluation, IMIM-Hospital del Mar, Passeig Marítim 25-29, 08003 Barcelona, Spain. Ldomingo@parcdesalutmar.cat
authors.forename: Laia
authors.initials: L
authors.lastname: Domingo
authors.forename: Anabel
authors.initials: A
authors.lastname: Romero
authors.forename: Francesc
authors.initials: F
authors.lastname: Belvis
authors.forename: Mar
authors.initials: M
authors.lastname: Sánchez
authors.forename: Joana
authors.initials: J
authors.lastname: Ferrer
authors.forename: Dolores
authors.initials: D
authors.lastname: Salas
authors.forename: Josefa
authors.initials: J
authors.lastname: Ibáñez
authors.forename: Alfonso
authors.initials: A
authors.lastname: Vega
authors.forename: Francesc
authors.initials: F
authors.lastname: Ferrer
authors.forename: M Soledad
authors.initials: MS
authors.lastname: Laso
authors.forename: Francesc
authors.initials: F
authors.lastname: Macià
authors.forename: Xavier
authors.initials: X
authors.lastname: Castells
authors.forename: Maria
authors.initials: M
authors.lastname: Sala
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000517:prevention & control; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000000981:diagnostic imaging* / Q000517:prevention & control; D016001:Confidence Intervals; D055088:Early Detection of Cancer / Q000295:instrumentation / Q000379:methods; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008327:Mammography / Q000379:methods*; D008403:Mass Screening / Q000458:organization & administration*; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D015397:Program Evaluation; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D013030:Spain