title: Effect of implementation of the mass breast cancer screening programme in older women in the Netherlands: population based study.
abstract: OBJECTIVE
  To assess the incidence of early stage and advanced stage breast cancer before and after the implementation of mass screening in women aged 70-75 years in the Netherlands in 1998.
  
  
  METHODS
  Prospective nationwide population based study.
  
  
  METHODS
  National cancer registry, the Netherlands.
  
  
  METHODS
  Patients aged 70-75 years with a diagnosis of invasive or ductal carcinoma in situ breast cancer between 1995 and 2011 (n=25,414). Incidence rates were calculated using population data from Statistics Netherlands.
  
  
  METHODS
  Incidence rates of early stage (I, II, or ductal carcinoma in situ) and advanced stage (III and IV) breast cancer before and after implementation of screening. Hypotheses were formulated before data collection.
  
  
  RESULTS
  The incidence of early stage tumours significantly increased after the extension for implementation of screening (248.7 cases per 100,000 women before screening up to 362.9 cases per 100,000 women after implementation of screening, incidence rate ratio 1.46, 95% confidence interval 1.40 to 1.52, P<0.001). However, the incidence of advanced stage breast cancers decreased to a far lesser extent (58.6 cases per 100,000 women before screening to 51.8 cases per 100,000 women after implementation of screening, incidence rate ratio 0.88, 0.81 to 0.97, P<0.001).
  
  
  CONCLUSIONS
  The extension of the upper age limit to 75 years has only led to a small decrease in incidence of advanced stage breast cancer, while that of early stage tumours has strongly increased.
authors.affiliation: Department of Surgery, Leiden University Medical Centre, PO Box 9600, Postzone K6-R, 2300 RC, Leiden, Netherlands Department of Gerontology and Geriatrics, Leiden University Medical Centre, Leiden, Netherlands.
authors.forename: Nienke A
authors.initials: NA
authors.lastname: de Glas
authors.affiliation: Department of Gerontology and Geriatrics, Leiden University Medical Centre, Leiden, Netherlands.
authors.forename: Anton J M
authors.initials: AJ
authors.lastname: de Craen
authors.affiliation: Department of Surgery, Leiden University Medical Centre, PO Box 9600, Postzone K6-R, 2300 RC, Leiden, Netherlands Department of Gerontology and Geriatrics, Leiden University Medical Centre, Leiden, Netherlands.
authors.forename: Esther
authors.initials: E
authors.lastname: Bastiaannet
authors.affiliation: Department of Surgery, Leiden University Medical Centre, PO Box 9600, Postzone K6-R, 2300 RC, Leiden, Netherlands.
authors.forename: Ester G
authors.initials: EG
authors.lastname: Op 't Land
authors.affiliation: Department of Surgery, Leiden University Medical Centre, PO Box 9600, Postzone K6-R, 2300 RC, Leiden, Netherlands Department of Gerontology and Geriatrics, Leiden University Medical Centre, Leiden, Netherlands.
authors.forename: Mandy
authors.initials: M
authors.lastname: Kiderlen
authors.affiliation: Department of Surgery, Leiden University Medical Centre, PO Box 9600, Postzone K6-R, 2300 RC, Leiden, Netherlands Department of Gerontology and Geriatrics, Leiden University Medical Centre, Leiden, Netherlands.
authors.forename: Willemien
authors.initials: W
authors.lastname: van de Water
authors.affiliation: Department of Research, Comprehensive Cancer Centre the Netherlands, Utrecht, Netherlands.
authors.forename: Sabine
authors.initials: S
authors.lastname: Siesling
authors.affiliation: Department of Medical Oncology, Haga Hospital, The Hague, Netherlands.
authors.forename: Johanneke E A
authors.initials: JE
authors.lastname: Portielje
authors.affiliation: Department of Radiology, Rijnland Hospital Leiderdorp, Netherlands.
authors.forename: Herman M
authors.initials: HM
authors.lastname: Schuttevaer
authors.affiliation: Department of Epidemiology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands.
authors.forename: Geertruida Truuske H
authors.initials: GT
authors.lastname: de Bock
authors.affiliation: Department of Surgery, Leiden University Medical Centre, PO Box 9600, Postzone K6-R, 2300 RC, Leiden, Netherlands.
authors.forename: Cornelis J H
authors.initials: CJ
authors.lastname: van de Velde
authors.affiliation: Department of Surgery, Leiden University Medical Centre, PO Box 9600, Postzone K6-R, 2300 RC, Leiden, Netherlands G.J.Liefers@lumc.nl.
authors.forename: Gerrit-Jan
authors.initials: GJ
authors.lastname: Liefers
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000453:epidemiology* / Q000473:pathology*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000453:epidemiology* / Q000473:pathology*; D055088:Early Detection of Cancer / Q000639:trends*; D005260:Female; D006801:Humans; D015994:Incidence; D008403:Mass Screening; D009367:Neoplasm Staging; D009426:Netherlands / Q000453:epidemiology; D011446:Prospective Studies; D012042:Registries