The development of a standardised imaging protocol to detect post endoscopic mucosal resection (EMR) recurrence or residual adenoma through the comparison of biopsies of the post EMR scar with endoscopic findings.

Removal of colonic polyps reduces colon cancer and although most polyps found are small, removal of large polyps can now be safely and effectively removed with wide field EMR. Residual polyp tissue is found at follow up colonoscopy in approximately 15% of cases however and remains a focus of attempts to improve EMR efficacy. All patients undergoing surveillance colonoscopy after EMR at Westmead Hospital Endoscopy unit will have steps of assessment and therapy of the scar recorded. Data will be entered into the large prospective audit database and also analysed separately. Data will be stored in coded format. The individual steps and the outcome of the scar interrogation and therapy will also be assessed and analysed. It is expected that these results will help guide the optimal approach to assessment and confirm the efficacy of therapy of recurrence further aiding the endoscopic approach to large colonic polyps.

Inclusion Criteria:

• Patients undergoing surveillance colonoscopy of a previously resected large sessile colonic polyp or laterally spreading tumour ≥20mm in size.
• Age > 18 years
• Able to give informed consent to involvement in the clinical study

Exclusion Criteria:

• Unable to provide informed consent for involvement

Patients who have had endoscopic mucosal resection of colonic polyps that are undergoing surveillance colonoscopy.