Possible advantages and drawbacks of adding flexible sigmoidoscopy to hemoccult-II in screening for colorectal cancer. A randomized study

Scand J Gastroenterol. 1999 Jan;34(1):73-8. doi: 10.1080/00365529950172862.


Background: Flexible sigmoidoscopy (FS) has been recommended as a screening method to reduce mortality from colorectal cancer (CRC). The present study evaluates the effect of adding FS to the fecal occult blood test Hemoccult-II (H-II) on diagnostic yield of colorectal neoplasia.

Methods: A total of 10,978 normal persons aged 50-75 years were invited to participate, 5495 persons being allocated at random to H-II and FS and 5483 to H-II alone.

Results: In spite of a lower compliance (40% versus 56%) for the combined procedure, the diagnostic yield of colorectal neoplasia was higher than for H-II alone (12 CRC versus 4 CRC, and 72 large adenomas versus 14). Within 24-62 months after screening there were fewer CRCs detected after H-II + FS than after H-II alone. The stage distribution was less favorable than in screen-detected cases.

Conclusion: One FS may not be an optimal way of screening, but FS deserves to be evaluated in randomized population studies including repeated H-II tests in the control arm.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Colonic Polyps / diagnosis
  • Colorectal Neoplasms / diagnosis*
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Middle Aged
  • Multiphasic Screening / methods*
  • Occult Blood*
  • Patient Compliance
  • Predictive Value of Tests
  • Sigmoidoscopy*