Letter to the editor regarding: Multicentre, prospective, randomised study comparing the diagnostic yield of colon capsule endoscopy versus CT colonography in a screening population (the TOPAZ study)

In a prospective, multicentre, randomised controlled trial in an average colon cancer risk population, the TOPAZ trial, Dr Cash and colleagues1 report that colon capsule endoscopy (CCE) revealed higher diagnostic yield (defined by finding a colonic polyp ≥6 mm that warrants an optical colonoscopy) and higher sensitivity compared with CT colonography (CTC). Based on these findings, Cash et al 1 advocate the use of CCE as a more accurate/superior diagnostic test among patients who cannot/prefer not to undergo optical colonoscopy. As abdominal radiologists experienced in CTC and as members of the American College of Radiology’s Colon Cancer Committee, we appreciate the effort by the authors in this clinical trial, but we have comments and concerns about the results, discussion and drawn conclusions: