Cold snare polypectomy (CSP) is now common practice and has proven to be a safe and effective technique for removal of diminutive polyps. Both thick and thin wire snares are now commonly used for CSP. However, because of their physical characteristics, thick wire snares might leave a higher percentage of residual adenoma at the resection site. Since this may result in a higher risk of recurrence, the technique needs to be optimized. Experts have suggested that a thin wire snare might be more efficient, with a lower risk of residual adenoma at the resection site and consequently a lower risk of recurrence and interval cancer.

Approximately 90% of polyps are smaller than 10 mm. Given the risk of transformation of adenomas into invasive cancer over years, it is important that these adenomas are completely resected.

This will be a double-blind, prospective, randomized controlled trial. All eligible patients referred for a colonoscopy will be able to participate. There will be 2 treatment arms, one arm will be treated with a thin wire snare and the other with a thick wire snare. Patients will be randomised through a computer generated programme and blinded for the type of snare used. The treatment arm will be disclosed to the proceduralist after introduction of the colonoscope into the rectum. After resection of the polyp the defect will be carefully examined by the proceduralist. In case of suspicion of residual adenomatous tissue, a re-excision will be performed. If there's a protrusion noticeable at the resection site, this will be biopsied. Ultimately, the margins of the defect will be biopsied on either side for histological confirmation of complete removal.

Inclusion Criteria:

• Patients able to give informed consent to involvement in trial. For patients who do not speak English, an interpreter will be asked to translate the informed consent
• Patients referred to Auburn Hospital Endoscopy Unit for a colonoscopy for whatever reason
• At least 1 lesion <10mm beyond the rectosigmoid junction without any endoscopic features of malignancy
• At least 1 lesion <10mm beyond the rectosigmoid junction that according to the proceduralist, can be safely removed with CSP

Exclusion Criteria:

• Current use of antiplatelets (excluding aspirin) or anticoagulants which have not appropriately been interrupted
• Known coagulopathy
• Pregnancy
• If any doubt about the benign character of the polyp, the patient will be excluded from the study