Cold or Hot Snare Endoscopic Mucosal Resection for 10-19mm Non-pedunculated Colorectal Polyps

A Prospective, Randomized, Non-inferiority Study to Compare Efficacy and Safety of Cold Snare Endoscopic Mucosal Resection and Hot Snare Endoscopic Mucosal Resection in Treatment for 10-19 mm Non-pedunculated Colorectal Polyps

This is a prospective, randomized, open-label, non-inferiority, multiple-center trial. Outpatients who are scheduled to undergo colonoscopy and found eligible polyps will be randomized to receive either cold snare endoscopic mucosal resection (CS-EMR) or hot snare endoscopic mucosal resection (HS-EMR). This study aims to compare the efficacy and safety of CS-EMR or HS-EMR for the resection of non-pedunculated colorectal polyps sized 10-19mm.

During CS-EMR, methylene blue-tinted epinephrine saline will be injected into the submucosal space around the lesion to lift the lesion. The polyp and 1-2mm of surrounding mucosa will then be closely snared and transected mechanically.

During HS-EMR, methylene blue-tinted epinephrine saline will be injected into the submucosal space around the lesion to lift the lesion. The snare will be placed around the lesion, and then cautery will be applied using the electrosurgical generator.

The resection is considered histologically complete if the lateral margins of the resected polyps are surrounded by normal tissue and the vertical margin is free of neoplasia tissue. If en-bloc resection is not achieved, 5 biopsies (4 biopsies obtained in a 4-quadrant fashion from the polypectomy site margins; 1 biopsy from the base) are applied to evaluate histological completeness of resection.

Any episode requiring emergency department presentation, hospitalization, or reintervention within 14 days

The duration from the first occurrence of injection needle under endoscope visual field to complete removal of the resected polyp

Inclusion Criteria: 18-80 years of age; undergo colonoscopy in the Digestive Endoscopy Center of Peking Union Medical College Hospital, Beijing Tsinghua Changgung Hospital or Seventh Medical Center, General Hospital of the Chinese People's Liberation Army; volunteer to participate in this study and sign informed consent; at least one polyp sized 10-19 mm (Paris classification Is or IIa) by colonoscopy. Exclusion Criteria: American Society of Anesthesiologists (ASA) status class 3 or above; poor bowel preparation (Boston bowel preparation scale < 6 points); known or endoscopic features indicating the submucous infiltration or malignancy; oral anti-coagulants, or antiplatelet agents, or known blood coagulation disorders, or bleeding tendency (platelets<50000 cells/mm3 or INR>1.5); a history of colorectal resection; emergency colonoscopy (hemodynamic instability and/or continued active gastrointestinal bleeding and/or requiring intensive care patients); inflammatory bowel disease, familial polyposis, and colorectal cancer; pregnancy or lactation; severe cardiopulmonary dysfunction, liver cirrhosis, chronic kidney disease, other malignant tumors, or severe infectious diseases.