title: Advanced breast cancer rates in the epoch of service screening: The 400,000 women cohort study from Italy.
abstract: The objective of this study was to evaluate if mammography screening attendance is associated with a reduction in late-stage breast cancer incidence.
  
  
  
  The cohort included over 400,000 Italian women who were first invited to participate in regional screening programmes during the 1990s and were followed for breast cancer incidence for 13 years. We obtained individual data on their exposure to screening and correlated this with total and stage-specific breast cancer incidence. Socio-economic status and pre-screening incidence data were used to assess the presence of self-selection bias.
  
  
  
  Overall, screening attendance was associated with a 10% excess risk of in situ and invasive breast cancer (IRR = 1.10; 95% confidence interval (CI): 1.06-1.14), which dropped to 5% for invasive cancers only (IRR = 1.05; 95% CI: 1.01-1.09). There were significant reductions among attenders for specific cancer stages; we observed a 39% reduction for T2 or larger (IRR = 0.61; 95% CI: 0.57-0.66), 19% for node positives (IRR = 0.81; 95% CI: 0.76-0.86) and 28% for stage II and higher (IRR = 0.72; 95% CI: 0.68-0.76). Our data suggest that the presence of self-selection bias is limited and, overall, invited women experienced a 17% reduction of advanced cancers compared with pre-screening rates.
  
  
  
  Comparing attenders' and non-attenders' stage-specific breast cancer incidence, we have estimated that screening attendance is associated with a reduction of nearly 30% for stages II+.
authors.affiliation: ISPO - Cancer Research and Prevention Institute, Clinical Epidemiology, Florence 50141, Italy.
authors.forename: Donella
authors.initials: D
authors.lastname: Puliti
authors.affiliation: Romagna Cancer Registry, Romagna Cancer Institute (IRST) IRCCS, Meldola, Forlì 47014, Italy.
authors.forename: Lauro
authors.initials: L
authors.lastname: Bucchi
authors.affiliation: Romagna Cancer Registry, Romagna Cancer Institute (IRST) IRCCS, Meldola, Forlì 47014, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Mancini
authors.affiliation: ISPO - Cancer Research and Prevention Institute, Clinical Epidemiology, Florence 50141, Italy.
authors.forename: Eugenio
authors.initials: E
authors.lastname: Paci
authors.affiliation: Veneto Cancer Registry, Veneto Region, Padua 35131, Italy.
authors.forename: Susanna
authors.initials: S
authors.lastname: Baracco
authors.affiliation: Planning and Control Staff, Local Health Unit, Reggio Emilia 42122, Italy; Arcispedale Santa Maria Nuova - IRCCS, Reggio Emilia 42122, Italy.
authors.forename: Cinzia
authors.initials: C
authors.lastname: Campari
authors.affiliation: Screening Center - Romagna Local Health Unit, Ravenna 48121, Italy.
authors.forename: Debora
authors.initials: D
authors.lastname: Canuti
authors.affiliation: Unit of Epidemiology and Risk Communication, Local Health Unit, Modena 41126, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Cirilli
authors.affiliation: Unit of Epidemiology, Health Promotion and Risk Communication, Department of Public Health, Bologna Local Health Authority, Bologna 40121, Italy.
authors.forename: Natalina
authors.initials: N
authors.lastname: Collina
authors.affiliation: Mammography Screening Programme, Local Health Unit, Parma 43100, Italy.
authors.forename: Giovanni Maria
authors.initials: GM
authors.lastname: Conti
authors.affiliation: Planning and Control Staff, Local Health Unit, Reggio Emilia 42122, Italy; Arcispedale Santa Maria Nuova - IRCCS, Reggio Emilia 42122, Italy.
authors.forename: Enza
authors.initials: E
authors.lastname: Di Felice
authors.affiliation: Screening Center - Romagna Local Health Unit, Ravenna 48121, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Falcini
authors.affiliation: Medical Oncology Unit and Cancer Registry of Parma Province, University Hospital of Parma, 43100 Parma, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Michiara
authors.affiliation: Mammography Screening Center, Local Health Unit, Modena 41124, Italy.
authors.forename: Rossella
authors.initials: R
authors.lastname: Negri
authors.affiliation: Romagna Cancer Registry, Romagna Cancer Institute (IRST) IRCCS, Meldola, Forlì 47014, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Ravaioli
authors.affiliation: Regional Health Department, Public Health Service, Emilia-Romagna Region, Bologna 40127, Italy.
authors.forename: Priscilla
authors.initials: P
authors.lastname: Sassoli De' Bianchi
authors.affiliation: Screening Center - Romagna Local Health Unit, Ravenna 48121, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Serafini
authors.affiliation: Veneto Cancer Registry, Veneto Region, Padua 35131, Italy.
authors.forename: Manuel
authors.initials: M
authors.lastname: Zorzi
authors.affiliation: ISPO - Cancer Research and Prevention Institute, Clinical Epidemiology, Florence 50141, Italy.
authors.forename: Adele
authors.initials: A
authors.lastname: Caldarella
authors.affiliation: Breast Centres Certification and Senonetwork Italia Onlus, Florence 50129, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Cataliotti
authors.affiliation: ISPO - Cancer Research and Prevention Institute, Clinical Epidemiology, Florence 50141, Italy. Electronic address: m.zappa@ispo.toscana.it.
authors.forename: Marco
authors.initials: M
authors.lastname: Zappa
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000517:prevention & control / Q000523:psychology; D015331:Cohort Studies; D055088:Early Detection of Cancer / Q000523:psychology / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D008327:Mammography / Q000523:psychology / Q000706:statistics & numerical data; D008403:Mass Screening / Q000523:psychology / Q000706:statistics & numerical data; D008875:Middle Aged; D000067455:No-Show Patients / Q000523:psychology / Q000706:statistics & numerical data; D010342:Patient Acceptance of Health Care / Q000523:psychology / Q000706:statistics & numerical data; D012959:Socioeconomic Factors
keywords: Advanced breast cancer; Cohort study; Mammography screening; Screening attendance; Screening effectiveness; Self-selection bias