Post-resection Treatment of Large Colon Polyps (SAP)

Prospective Randomized Controlled Trial Describing the Recurrence Rate of Adenomas in Sessile or Flat Colonic Lesions 15mm or Larger Receiving Post-resection Site Treatment With Snare Tip Soft Coagulation or Argon Plasma Coagulation

Patients who have provided informed consented and are scheduled to undergo endoscopic mucosal resection (EMR) of lesions 15mm and larger will be randomized to STSC (80 W, Effect 5) vs APC (preferred settings) vs No Treatment of the perimeter of the EMR site.

Data regarding polyp morphology, location & shape will be recorded in addition to procedure and treatment length. Injection fluid use and clipping will also be recorded in addition to any procedural complications. All randomized subjects will receive a 30-day post procedure follow-up phone call and be scheduled, as per the standard of care, to receive a standard follow-up colonoscopy procedure after the initial procedure. The investigators will measure the rate of recurrence by endoscopic visualization of the EMR site at the first follow-up using endoscopic magnification and electronic chromoendoscopy, as well as systematic biopsy of the scars.

Patients will be randomized to Argon Plasma Coagulation vs Snare Tip Soft Coagulation vs no treatment

Following polyp removal using standard of care methods, Argon Plasma Coagulation (APC) will be applied to the perimeter of the resection site before any clips are added.

Following polyp removal using standard of care methods, Snare Tip Soft Coagulation (STSC) will be applied to the perimeter of the resection site before any clips are added.

Following polyp removal using standard of care methods, neither APC nor STSC will be applied to the perimeter of the resection site. Clips may be added at the discretion of the PI.

The recurrence rate of adenomas at the site of any qualifying, previously resected lesions will be measured at the first follow-up colonoscopy

To look at the number of complications for each randomization arm as assessed through a 30 day follow-up phone call

Cost analysis detailing the effectiveness of the treatment versus the cost of each therapeutic device (argon probe vs. snare)

Inclusion Criteria: 25 years and older Ability to provide informed consent Undergoing colonoscopy for screening, surveillance, diagnostic reasons, or removal of a lesion Exclusion Criteria: Pedunculated lesions Inflammatory bowel disease Inability to provide informed consent Lesions less than 15mm in largest dimension

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Brooker JC, Saunders BP, Shah SG, Thapar CJ, Suzuki N, Williams CB. Treatment with argon plasma coagulation reduces recurrence after piecemeal resection of large sessile colonic polyps: a randomized trial and recommendations. Gastrointest Endosc. 2002 Mar;55(3):371-5. doi: 10.1067/mge.2002.121597.

Tate DJ, Bahin FF, Desomer L, Sidhu M, Gupta V, Bourke MJ. Cold-forceps avulsion with adjuvant snare-tip soft coagulation (CAST) is an effective and safe strategy for the management of non-lifting large laterally spreading colonic lesions. Endoscopy. 2018 Jan;50(1):52-62. doi: 10.1055/s-0043-119215. Epub 2017 Oct 11.