Diagnostic accuracy of capsule endoscopy compared to colonoscopy for polyp detection: systematic review and meta-analyses.

Kjølhede, Tue; Ølholm, Anne Mette; Kaalby, Lasse; Kidholm, Kristian; Qvist, Niels; Baatrup, Gunnar

BACKGROUND Colon capsule endoscopy (CCE) is a technology that might contribute to colorectal cancer (CRC) screening programs as a filter test between fecal immunological test and standard colonoscopies (SC). The aim was to systematically review the literature for studies investigating the diagnostic yield of 2nd generation CCE compared to SC. METHODS A systematic literature search was performed in PubMed, Embase and Web of Science. Study characteristics including quality of bowel preparation and completeness of CCE transits were extracted. Per-patient sensitivity and specificity were extracted for polyps (any size; ≥ 10mm, ≥6 mm) and lesion characteristics. Meta-analyses of diagnostic yield were performed. RESULTS The literature search revealed 1077 unique papers and 12 studies were included. These included 2199 in total of which 1898 patients were available for analyses. The rate of patients with adequate quality of the bowel preparation varied from 40% to 100%. The rates of complete CCE transits varied from 57% to 100%. Our meta-analyses demonstrated that mean [95% confidence interval] sensitivity, specificity and diagnostic odds ratio was 0.85 [0.73;0.92], 0.85 [0.70;0.93] and 30.5 [16.2;57.2], respectively for polyps of any size, 0.87 [0.82;0.90], 0.95 [0.92;0.97] and 136.0 [70.6;262.1], respectively for polyps ≥ 10mm and 0.87 [0.83;0.90], 0.88 [0.75;0.95] and 51.1 [19.8;131.8], respectively for polyps ≥ 6mm. No serious adverse events were reported for CCE. CONCLUSION In conclusion, CCE has a high sensitivity and specificity for per-patient polyps compared to SC. However, the relatively high rate of incomplete investigations limits the application of CCE in a CRC-screening setting.