Suspicious macroscopic features of small malignant colorectal polyps

Area of Science:

• Gastroenterology
• Endoscopic Imaging
• Colorectal Cancer Detection

Background:

• Colorectal polyps are common, with a small percentage being malignant.
• Early detection of malignant polyps is crucial for improving patient outcomes.
• Small malignant polyps (<10 mm) can be challenging to identify during standard colonoscopy.

Purpose of the Study:

• To retrospectively analyze video recordings of small malignant polyps (<10 mm).
• To identify suspicious macroscopic features indicative of malignancy in white light endoscopy.
• To evaluate the diagnostic performance of recognizing these features.

Main Methods:

• Review of screening colonoscopy recordings from a single tertiary center (June 2009 - December 2012).
• Analysis of malignant polyps <10 mm for specific morphological features (e.g., irregular contours, central depression, chicken skin sign).
• Blinded assessment by experienced endoscopists to determine sensitivity and specificity.

Main Results:

• Only 5 of 8651 subjects (0.06%) had malignant polyps <10 mm; only one was initially flagged as suspicious.
• Review of recordings revealed suspicious macroscopic features in the remaining malignant polyps.
• Sensitivity and specificity for diagnosing malignant polyps were 73.21% and 85.35% when at least two suspicious features were present.

Conclusions:

• Small malignant colorectal polyps exhibit recognizable suspicious macroscopic features on white light endoscopy.
• These features are often overlooked by endoscopists, highlighting a potential gap in diagnostic accuracy.
• Improved recognition of these features could enhance the detection rates of early-stage colorectal cancer.