Cold vs Hot Snare Endoscopic Mucosal Resection for Large Flat Non-Pedunculated Colorectal Polyps

In the realm of colonoscopic resection, two guiding principles are paramount — first, the decision to resect a polyp; second, ensuring the resection is complete and safe. It is advised to avoid cold biopsy polypectomy for small polyps owing to the risk of incomplete resection. Instead, cold snare polypectomy is recommended for the safe and complete removal of small adenomas 10 mm or smaller in size.

Recent advances raise the question of whether cold snare endoscopic mucosal resection (EMR) after submucosal injection can be applied to larger polyps.

The work of Dr. Michael J. Bourke and his team highlights that, although cold snare EMR (CS-EMR) exhibits a safety profile superior to that of hot snare EMR (HS-EMR), it carries a recurrence risk of around 20% for large non-pedunculated colorectal polyps. This finding is noteworthy, given that these procedures were performed by advanced-trained gastroenterologists at a tertiary center specializing in colorectal EMR.

Current literature suggests that cold resections should be reserved for small polyps and sessile serrated lesions, with caution exercised when dysplasia is suspected. The recurrence rate of adenomas post CS-EMR, affecting 1 in 5 patients, remains a significant concern. Thus, although CS-EMR is a safer option, the high recurrence rate necessitates careful consideration given the advances in HS-EMR. Over the past decade, adjuvant techniques, including thermal ablation of resection edges and complete clip closure of defects post HS-EMR, have significantly reduced recurrence and complication rates to under 5%.

For now, our practice protocol remains clear — utilize HS-EMR with margin ablation and clip closure for large adenomas and CS-EMR for smaller polyps to optimize patient outcomes and manage resources effectively. This balanced approach ensures both efficacy and safety in the complex landscape of colonoscopic resection.