The goal of this clinical trial is to clarify the role of adjuvant thermal ablation for non-thermal endoscopic mucosal resection (EMR) of large (≥20mm) flat colorectal polyps (so-called laterally spreading lesions \[LSLs\]).
The hypothesis is that adding adjuvant thermal ablation to non-thermal EMR (vs no ablation) will result in lower lesion recurrence rates at 6-month follow-up, and non-inferior adverse events (AE) rates 14 days post EMR.
For participants with planned EMR, endoscopists will perform non-thermal EMRs as per standard of care and:
* adjuvant thermal ablation will either not be performed (control group), or will be applied to the base and outside margins of the resection site (experimental group); * then, all patients will be contacted 14-44 days after EMR, to verbally ascertain the occurrence of AEs; * then, all patients will undergo a first follow-up colonoscopy at 6 months after initial conoloscopy to assess lesion recurrence; * finally, all patients will undergo a second and final colonoscopy 18 months after EMR.
Adult patients
Undergoing EMR for large (≥20 mm) colorectal LSL
Providing written and informed consent for study participation
Inflammatory bowel disease
Non-elective colonoscopy
Poor general health (American Society of Anesthesiologists classification >III)
Coagulopathy or thrombocytopenia (international normalized ration ≥1.5 or platelets <50*10^9/L)