Endoscopic resection (ER) of colorectal polyps reduces the incidence and mortality of colorectal cancer (CRC).1,2 The majority (>90%) of colonic polyps are small (<10mm) and are definitively, efficiently and safely removed by cold snare polypectomy.3,4 Large (≥20mm) non-pedunculated colorectal polyps (LNPCP) account for 1-2% of all polyps detected at colonoscopy and are more challenging to remove endoscopically.5 Traditionally, decision making in the management of colonic polyps was based solely on size. However, over the last decade lesion complexity has increasingly been defined by a composite of multiple factors including lesion morphology, location, endoscopic access and prior attempts at resection.6 These factors are associated with higher rates of incomplete resection, harbouring submucosal invasive cancer (SMIC) and adverse events (AE).

In expert centres, the overwhelming majority (>95%) of LNPCP can be removed by endoscopic mucosal resection (EMR), which is recommended over surgery due to its excellent technical success, superior safety and cost effectiveness.3,5,7, 8, 9, 10 Modification of this technique, as well as the application of ancillary and alternative ER methods, have enabled increasingly complex lesions to be safely and effectively resected endoscopically without impacting on procedural morbidity.11, 12, 13, 14, 15, 16, 17 The expert tissue resection endoscopist is fundamentally an individual with adequate training and access to appropriate resources, who fully embraces and employs ER within the evolving evidence framework to cure neoplastic lesions. Herein, we describe an evidence-based approach for the endoscopic management of complex LNPCP.