title: Breast cancer detection risk in screening mammography after a false-positive result.
abstract: BACKGROUND
  False-positives are a major concern in breast cancer screening. However, false-positives have been little evaluated as a prognostic factor for cancer detection. Our aim was to evaluate the association of false-positive results with the cancer detection risk in subsequent screening participations over a 17-year period.
  
  
  METHODS
  This is a retrospective cohort study of 762,506 women aged 45-69 years, with at least two screening participations, who underwent 2,594,146 screening mammograms from 1990 to 2006. Multilevel discrete-time hazard models were used to estimate the adjusted odds ratios (OR) of breast cancer detection in subsequent screening participations in women with false-positive results.
  
  
  RESULTS
  False-positives involving a fine-needle aspiration cytology or a biopsy had a higher cancer detection risk than those involving additional imaging procedures alone (OR = 2.69; 95%CI: 2.28-3.16 and OR = 1.81; 95%CI: 1.70-1.94, respectively). The risk of cancer detection increased substantially if women with cytology or biopsy had a familial history of breast cancer (OR = 4.64; 95%CI: 3.23-6.66). Other factors associated with an increased cancer detection risk were age 65-69 years (OR = 1.84; 95%CI: 1.67-2.03), non-attendance at the previous screening invitation (OR = 1.26; 95%CI: 1.11-1.43), and having undergone a previous benign biopsy outside the screening program (OR = 1.24; 95%CI: 1.13-1.35).
  
  
  CONCLUSIONS
  Women with a false-positive test have an increased risk of cancer detection in subsequent screening participations, especially those with a false-positive result involving cytology or biopsy. Understanding the factors behind this association could provide valuable information to increase the effectiveness of breast cancer screening.
authors.affiliation: Department of Epidemiology and Evaluation, Institut Municipal d'Investigació Mèdica-Parc de Salut Mar, Mar Teaching Hospital, 25-29 Passeig Marítim, 08003 Barcelona, Spain. xcastells@parcdesalutmar.cat
authors.forename: X
authors.initials: X
authors.lastname: Castells
authors.forename: M
authors.initials: M
authors.lastname: Román
authors.forename: A
authors.initials: A
authors.lastname: Romero
authors.forename: J
authors.initials: J
authors.lastname: Blanch
authors.forename: R
authors.initials: R
authors.lastname: Zubizarreta
authors.forename: N
authors.initials: N
authors.lastname: Ascunce
authors.forename: D
authors.initials: D
authors.lastname: Salas
authors.forename: A
authors.initials: A
authors.lastname: Burón
authors.forename: M
authors.initials: M
authors.lastname: Sala
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging; D015331:Cohort Studies; D055088:Early Detection of Cancer / Q000379:methods; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D008327:Mammography / Q000379:methods*; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors