Yield of adenomas and colorectal cancers within 5 years of a negative colonoscopy: are the guidelines guiding?

ANZ J Surg. 2018 Jan;88(1-2):E1-E5. doi: 10.1111/ans.13631. Epub 2016 Jun 14.

Abstract

Background: Screening for colorectal cancers outside the recommended guidelines presents a considerable burden to resource management in many public hospitals. The aim of this study is to evaluate the frequency, indications and outcomes for repeat colonoscopy performed within 5 years of a negative colonoscopy.

Methods: A retrospective review of all colonoscopies at Nambour Hospital in 2008 was performed to identify those with a negative colonoscopy. The charts of patients undergoing repeat colonoscopy at the same institution within 5 years of a negative colonoscopy were examined further, and data obtained regarding indications and outcomes of subsequent colonoscopies.

Results: A total of 616 colonoscopies were identified, 427 (69.3%) were negative for adenoma and carcinoma. Of these patients, 74 (17.3%) underwent a repeat colonoscopy at Nambour Hospital within 5 years. Eighteen out of 74 (24.3%) were outside guideline recommendation. Overall, one patient (1.4%) had cancer and 11 patients (14.9%) had polyps detected at repeat colonoscopy. Most of the polyps detected had low-risk features and were detected in the fourth and fifth years of the study period.

Conclusion: The yield of a second colonoscopy within 5 years of a good-quality negative colonoscopy is low but not zero. In the absence of new concerning symptoms or other risk factors, patients can be reassured and guidelines adhered to.

Keywords: adenomas; colorectal cancers; negative colonoscopy.

MeSH terms

  • Adenoma / diagnosis*
  • Adult
  • Aged
  • Aged, 80 and over
  • Colonic Neoplasms / diagnosis*
  • Colonoscopy*
  • Early Detection of Cancer
  • Female
  • Humans
  • Male
  • Middle Aged
  • Patient Selection
  • Predictive Value of Tests
  • Retrospective Studies