The Australian Colonic Advanced Mucosal Neoplasia and Endoscopic Resection Study

To enhance understanding of the risk factors for AMN, improve lesion assessment and prediction of submucosal invasive cancer, improve endoscopic resection efficacy, reduce complications of WF-EMR and improve the understanding of the progression of large lesions to cancer

The Australian Colonic Endoscopic Mucosal Resection study (ACE), is a multicentre prospective observational study which examined WF-EMR of colonic AMN (Ethics approval No. HREC JH/TG 2008/9/6.1(2858)). This project now has an extensive dataset from 8 leading colonic endoscopic resection centres in Australia on more than 1500 lesions resected over 4 years since June 2008. The ACE study has been successful in addressing several aspects of the resection of AMN, resulting in several high profile papers in internationally recognised journals. The collection of this data has produced robust information on the efficacy of the procedure4, recurrence rates7, bleeding complications8 and mortality when compared to surgery5. Single centre analysis of the ACE dataset at Westmead has also allowed insights into how to refine the procedure to improve outcomes. The target sign is now a recognised indication for the placement of clips to prevent perforation9, CO2 insufflation for WF-EMR has been shown to be superior to air insufflation10 and succinylated gelatin (Gelofusine®) has been shown to be superior to normal saline as a submucosal lifting agent11. There remain a number of unanswered questions regarding the endoscopic resection of large sessile lesions and expanding the ACE dataset in a new cohort of patients will allow these to be addressed. Enhancing the prediction of submucosal invasive cancer, advanced lesion classification, refinement of the assessment of deep injury, submucosal injectate constituents, the optimum electrosurgical resection methods, prevention and prophylaxis of bleeding, and subtype analyses of the different histological groups comprising AMN will be examined.

Inclusion Criteria: * Patients referred for endoscopic resection of a 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