Innovations in endoscopic resection of laterally spreading non-pedunculated colorectal polyps to improve clinical outcomes

Abstract

Introduction/Aims

Over the past two decades, there have been significant advancements in endoscopic resection (ER). ER is now considered the first-line technique for resection of all benign and some malignant lesions. Compared to surgery, ER is cost-effective with lower morbidity and mortality. Cold snare polypectomy (CSP) is safer and equally efficacious compared to hot snare polypectomy (HSP) for the removal of colonic polyps <10mm. The superior safety profile of CSP holds promise for the resection of laterally spreading non-pedunculated colorectal polyps ≥20mm (LNPCPs). However, large randomised controlled trials comparing Cold-Endoscopic Mucosal Resection (C-EMR) to conventional EMR are lacking.

This thesis aims to address these knowledge deficiencies.

Methods

Multi-centre prospective trials were conducted to address the aims outlined above. All studies received ethics approval. Written, informed consent was obtained from each participant.

Results

C-EMR has a higher recurrence rate compared to EMR for LNPCPs (17.2% vs 1.1%, p<0.001). Using mathematical modelling, polyp area was shown to increase quadratically with increasing polyp radius. This results in disproportionately more sequential snare resections, with each resection carrying a risk of leaving residual adenoma. Lesion size, location, and morphology are the most important factors when predicting lesion histology. We found that cancer is 2.5 times more common in the rectum compared to the rest of the colon (Odds ratio 1.77, Confidence interval 1.25–2.53, p<0.001). Full-thickness resection of small tumours can be effectively achieved with durable long-term outcomes.

Conclusions

ER should be considered first-line for the removal of neoplastic gastrointestinal lesions, including early cancers. Results from this thesis improve our understanding of ER techniques and their role within the ER algorithm.