title: Faecal immunochemical test accuracy in patients referred for surveillance colonoscopy: a multi-centre cohort study.
abstract: BACKGROUND
  Given the increasing burden on colonoscopy capacity, it has been suggested that faecal immunochemical test (FIT) results could guide surveillance colonoscopy intervals. Against this background, we have evaluated the test accuracy of single and double FIT sampling to detect colorectal cancer (CRC) and/or advanced adenomas in an asymptomatic colonoscopy-controlled high-risk population.
  
  
  METHODS
  Cohort study of asymptomatic high-risk patients (personal history of adenomas/CRC or family history of CRC), who provided one or two FITs before elective colonoscopy. Test accuracy of FIT for detection of CRC and advanced adenomas was determined (cut-off level 50 ng/ml).
  
  
  RESULTS
  1,041 patients provided a FIT (516 personal history of adenomas, 172 personal history of CRC and 353 family history of CRC). Five CRCs (0.5%) and 101 advanced adenomas (9.7%) were detected by colonoscopy. Single FIT sampling resulted in a sensitivity, specificity, PPV and NPV for CRC of 80%, 89%, 3% and 99.9%, respectively, and for advanced adenoma of 28%, 91%, 24% and 92%, respectively. Double FIT sampling did not result in a significantly higher sensitivity for advanced neoplasia. Simulation of multiple screening rounds indicated that sensitivity of FIT for advanced adenoma could reach 81% after 5 screening rounds.
  
  
  CONCLUSIONS
  In once-only FIT sampling before surveillance colonoscopy, 70% of advanced neoplasia were missed. A simulation approach indicates that multiple screening rounds may be more promising in detecting advanced neoplasia and could potentially alleviate endoscopic burden.
authors: Gastroenterology and Hepatology, VU University Medical Centre, Amsterdam, The Netherlands. js.terhaar@vumc.nl
authors: Jochim S
authors: JS
authors: Terhaar sive Droste
authors: Sietze T
authors: ST
authors: van Turenhout
authors: Frank A
authors: FA
authors: Oort
authors: René W M
authors: RW
authors: van der Hulst
authors: Vincent A
authors: VA
authors: Steeman
authors: Usha
authors: U
authors: Coblijn
authors: Lisette
authors: L
authors: van der Eem
authors: Ruud
authors: R
authors: Duijkers
authors: Anneke A
authors: AA
authors: Bouman
authors: Gerrit A
authors: GA
authors: Meijer
authors: Annekatrien C T M
authors: AC
authors: Depla
authors: Pieter
authors: P
authors: Scholten
authors: Ruud J L F
authors: RJ
authors: Loffeld
authors: Veerle M H
authors: VM
authors: Coupé
authors: Chris J J
authors: CJ
authors: Mulder
mesh_terms: D000236:Adenoma / Q000175:diagnosis* / Q000453:epidemiology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000453:epidemiology; D003955:Diagnostic Tests, Routine / Q000379:methods*; D062665:Epidemiological Monitoring; D005243:Feces; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity