Risk factors for advanced neoplasia within subcentimetric polyps: implications for diagnostic imaging

Area of Science:

• Gastroenterology
• Colorectal Cancer Screening
• Medical Diagnostics

Background:

• CT colonography and capsule endoscopy are used for colonic lesion detection.
• Work-up strategies for subcentimetric lesions remain controversial.
• Identifying risk factors for advanced neoplasia (AN) in these lesions is crucial.

Purpose of the Study:

• To identify risk indicators for advanced neoplasia (AN) in subcentimetric polyps.
• To develop and validate a risk index for AN in subcentimetric polyps.
• To inform clinical decision-making for patients with small colonic lesions.

Main Methods:

• Analysis of over 1 million colonoscopies to classify lesions (intermediate: 5-9 mm, diminutive: ≤4 mm).
• Logistic regression models developed to identify risk factors for AN (defined as high-grade dysplasia, villous histology, or cancer).
• Risk index generated and validated; number needed to screen (NNS) calculated.

Main Results:

• 13% of intermediate and 3.7% of diminutive lesions showed AN.
• Higher risk of AN in intermediate vs. diminutive lesions (OR 3.1).
• Key risk factors identified: older age (≥85), male sex, blood in stool (occult/overt), >4 lesions, and pedunculated morphology.

Conclusions:

• A validated risk index for subcentimetric lesions was established.
• The findings provide a framework for managing patients with small colonic polyps detected via imaging.
• This risk stratification aids in optimizing diagnostic work-up and patient care.