Diagnostic Value of Adding Magnifying Chromoendoscopy to Magnifying Narrow-Band Imaging Endoscopy for Colorectal...

Area of Science:

• Gastroenterology
• Endoscopy
• Oncology

Background:

• Optical diagnosis of colorectal polyps is crucial for guiding treatment decisions.
• Magnifying narrow-band imaging endoscopy (M-NBI) is a valuable tool, but its diagnostic accuracy can be limited.
• Further enhancement of diagnostic capabilities is needed for accurate polyp characterization.

Purpose of the Study:

• To evaluate the added diagnostic value of magnifying chromoendoscopy (MCE) following magnifying narrow-band imaging endoscopy (M-NBI) for optical diagnosis of colorectal polyps.
• To compare the diagnostic accuracy of M-NBI alone versus MCE combined with M-NBI in identifying colorectal cancer (CRC) with deep invasion (≥T1b).

Main Methods:

• A multicenter prospective study involving 1173 colorectal lesions across 9 facilities in Japan and Germany.
• Optical diagnosis was performed sequentially: M-NBI first, followed by MCE for selected lesions.
• Diagnostic accuracy for predicting CRC with deep invasion was compared against histological findings.

Main Results:

• Magnifying chromoendoscopy (MCE) significantly improved sensitivity for detecting colorectal cancer with deep invasion (≥T1b) compared to M-NBI alone (77.4% vs 63.1%).
• Overall diagnostic accuracy for ≥T1b CRC was 91.1% with MCE versus 90.2% with M-NBI alone.
• The additional benefit of MCE was most pronounced in lesions with low diagnostic confidence on M-NBI or those initially suspected of deep invasion.

Conclusions:

• Magnifying chromoendoscopy (MCE) provides significant additional value to magnifying narrow-band imaging endoscopy (M-NBI) in the optical diagnosis of colorectal polyps.
• MCE is recommended for lesions where M-NBI provides low diagnostic confidence or when deep submucosal invasion (≥T1b) is suspected.