Diagnostic value of CT-colonography as compared to colonoscopy in an asymptomatic screening population: a meta-analysis

Eur Radiol. 2011 Aug;21(8):1747-63. doi: 10.1007/s00330-011-2104-8. Epub 2011 Apr 1.

Abstract

Objectives: Previous meta-analyses on CT-colonography included both average and high risk individuals, which may overestimate the diagnostic value in screening. A meta-analysis was performed to obtain the value of CT-colonography for screening.

Methods: A search was performed using PubMed, Embase and Cochrane. Article selection and critical appraisal was done by two reviewers.

Inclusion criteria: prospective, randomized trials or cohort studies comparing CT-colonography with colonoscopy (≥50 participants), ≥95% average risk participants ≥50 years. Study characteristics and 2 × 2 contingency Tables were recorded. Sensitivity and specificity estimates were calculated per patient and per polyp (≥6 mm, ≥10 mm), using univariate and bivariate analyses.

Results: Five of 1,021 studies identified were included, including 4,086 participants (<1% high risk). I(2)-values showed substantial heterogeneity, especially for 6-9 mm polyps and adenomas: 68.1% vs. 78.6% (sensitivity per patient). Estimated sensitivities for patients with polyps or adenomas ≥ 6 mm were 75.9% and 82.9%, corresponding specificities 94.6% and 91.4%. Estimated sensitivities for patients with polyps or adenomas ≥ 10 mm were 83.3% and 87.9%, corresponding specificities 98.7% and 97.6%. Estimated sensitivities per polyp for advanced adenomas ≥ 6 mm and ≥ 10 mm were 83.9% and 83.8%.

Conclusion: Compared to colonoscopy, CT-colonography has a high sensitivity for adenomas ≥ 10 mm. For (advanced) adenomas ≥ 6 mm sensitivity is somewhat lower.

Publication types

  • Comparative Study
  • Meta-Analysis

MeSH terms

  • Aged
  • Colonography, Computed Tomographic*
  • Colonoscopy*
  • Colorectal Neoplasms / diagnostic imaging*
  • Colorectal Neoplasms / pathology
  • Humans
  • Mass Screening*
  • Middle Aged
  • Sensitivity and Specificity