title: Comparing attendance and detection rate of colonoscopy with sigmoidoscopy and FIT for colorectal cancer screening.
abstract: OBJECTIVE
  We conducted a study to estimate population coverage and detection rate (DR) achievable through different strategies of colorectal cancer (CRC) screening.
  
  
  METHODS
  A population-based multicenter randomized trial comparing 3 strategies was used: (1) biennial immunologic fecal occult blood test (FIT), (2) "once only" sigmoidoscopy (FS), and (3) "once only" colonoscopy (TC). A random sample of men and women, aged 55 to 64 years, was drawn from general practitioners' (GP) rosters. Eligible subjects, randomized within GP, were mailed a personal invitation. Nonresponders in groups 2 and 3 were invited again at 12 and 24 months. Screenees with "high-risk" distal polyps (villous component >20%, high-grade dysplasia, CRC, size >or=10 mm, >2 adenomas) at FS, or with positive FIT, were referred for TC.
  
  
  RESULTS
  The attendance rate was 32.3% (1965/6075) for FIT, 32.3% (1944/6018) for FS, 26.5% (1597/6021) for TC. FIT detected 2 patients with CRC (0.1%) and 21 with an advanced adenoma (1.1%). The corresponding figures were as follows: 12 (0.6%) and 86 (4.5%) patients, respectively, for FS; 13 (0.8%) and 100 (6.3%) patients, respectively, for TC. To detect 1 advanced neoplasm, it would be necessary to invite 264 people with FIT, 60 with FS, 53 with TC. FS would have detected 27.3% of the proximal advanced neoplasms detected at TC. Assuming the same participation rate at TC as at FS, 48 TCs would be necessary to detect 1 additional advanced neoplasm missed by FS.
  
  
  CONCLUSIONS
  When participants are offered 1 screening test, participation is lower in a TC than in an FS program. However, DR of advanced neoplasia is higher with TC.
authors.affiliation: CPO Piemonte, Torino, Italy. nereo.segnan@cpo.it
authors.forename: Nereo
authors.initials: N
authors.lastname: Segnan
authors.forename: Carlo
authors.initials: C
authors.lastname: Senore
authors.forename: Bruno
authors.initials: B
authors.lastname: Andreoni
authors.forename: Alberto
authors.initials: A
authors.lastname: Azzoni
authors.forename: Luigi
authors.initials: L
authors.lastname: Bisanti
authors.forename: Alessandro
authors.initials: A
authors.lastname: Cardelli
authors.forename: Guido
authors.initials: G
authors.lastname: Castiglione
authors.forename: Cristiano
authors.initials: C
authors.lastname: Crosta
authors.forename: Andrea
authors.initials: A
authors.lastname: Ederle
authors.forename: Alberto
authors.initials: A
authors.lastname: Fantin
authors.forename: Arnaldo
authors.initials: A
authors.lastname: Ferrari
authors.forename: Mario
authors.initials: M
authors.lastname: Fracchia
authors.forename: Franco
authors.initials: F
authors.lastname: Ferrero
authors.forename: Stefano
authors.initials: S
authors.lastname: Gasperoni
authors.forename: Serafino
authors.initials: S
authors.lastname: Recchia
authors.forename: Mauro
authors.initials: M
authors.lastname: Risio
authors.forename: Tiziana
authors.initials: T
authors.lastname: Rubeca
authors.forename: Giorgio
authors.initials: G
authors.lastname: Saracco
authors.forename: Marco
authors.initials: M
authors.lastname: Zappa
mesh_terms: D000236:Adenoma / Q000175:diagnosis; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000453:epidemiology; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D009780:Occult Blood; D010349:Patient Compliance; D018579:Patient Selection; D015995:Prevalence; D012812:Sigmoidoscopy