The CFP technique is performed as follows. A biopsy forceps is passed through the working channel of the endoscope. The jaws of the forceps are placed over the polyp tissue, and the polyp is captured and removed with mechanical pressure. The advantages of CFP are the following: easy, simple technique to apply; short procedure time; relatively low cost; easy tissue retrieval; and low rate of complications, such as bleeding or perforation. Unfortunately, this procedure is associated with significant rates of incomplete polyp resection [8]. The endoscopist should meticulously inspect the resection site and remove any remaining tissue to confirm that complete resection has been achieved. Notably, previous trials revealed a marked incomplete resection rate following what was considered complete removal of a polyp (29% to 38%) [9-11]. The reason for this rather high incomplete resection rate might be that minor bleeding after the initial bite can obstruct the visual field of a polypectomy site. To increase the complete resection rate, proposed alternatives to conventional CFP include the use of jumbo biopsy forceps (Radial Jaw 4 Single-Use Jumbo Biopsy Forceps; Boston Scientific Corp., Marlborough, MA, USA) [12] or narrow-band imaging evaluation of remnant tissue following CFP [13].

HFP is analogous to CFP except it involves applying an electric current to the forceps. The technique of HFP involves the following. A biopsy forceps is passed through the working channel of an endoscope. The tip of the polyp should be captured and tented away from the colonic wall to prevent perforation. The colonic lumen should be slightly deflated, and electrocautery is then applied. Application of electrical current by a coagulation wave removes the polyp and burns the surrounding tissue. The disadvantages of this method are a 17% to 34% risk of residual polyp; increased risk of coagulation syndrome, perforation, and delayed bleeding; and impaired histological evaluation of the biopsy specimen [14-16]. The right colon is particularly vulnerable to transmural injury. Great care must be taken when performing HFP in the right colon. For these reasons, the Korean guidelines for colonoscopic polypectomy do not routinely recommend HFP for the removal of diminutive and small polyps [17].

Cold snare polypectomy (CSP) has recently been accepted as the ideal method for the resection of diminutive and small polyps. The technique of CSP is performed as follows. First, the lesion should be placed at the 5 o’clock position. The snare opens and encircles the polyp without air aspiration. Then, the snare slowly captures the polyp with at least 1 to 2 mm of surrounding normal tissue. The polyp is guillotined and should not be lifted or tented until complete closure is achieved. The polyp can then be suctioned through the working channel into the trap [18]. The advantages of CSP are a short procedure time, high complete resection rate, and low complication rate. In a recent prospective, randomized trial, CSP with a snare exclusively designed as a cold snare (Exacto cold snare; US Endoscopy, Mentor, OH, USA) resulted in complete polyp removal more often than did CSP with a traditional snare [19]. Snares exclusively designed as cold snares (with features such as thinner wires or a different shield shape) may be more efficient for resection and easier to use for cutting than traditional snares.

Hot snare polypectomy (HSP) is a polyp removal method in which a polyp is grasped by a snare and then removed by electrocautery. Electrocautery can cause damage to the proper muscle layer and then lead to coagulation syndrome or perforation. Therefore, HSP should be used with some caution in comparison to CSP. First, to avoid grasping excess normal tissue, a polyp with minimal normal tissue should be captured by the snare. Second, the ensnared polyp should be tented away from the colonic wall and the lumen should be deflated prior to the application of electrocautery to minimize the risk of transmural injury. The following are three types of electric currents used in HSP: pure cut, coagulation, and blended. There is currently no consensus regarding the optimal type of current that should be used. Generally, a blended or coagulation current, rather than a pure cut current, is recommend for polypectomy because of the bleeding risk.

Endoscopic mucosal resection (EMR) has generally become an accepted curative treatment for large polyps up to 20 mm in size. EMR allows the resection of the mucosa, muscularis mucosa, and a part or even all of the submucosa. The technique of EMR technique involves the following. First, the polyp should be elevated by a submucosal injection. The elevated polyp is grasped in a polypectomy snare and removed by an electric current. The submucosal cushion reduces the risk of perforation and improves the chances of complete resection. Therefore, it is vital to maintain sufficient elevation of the lesion throughout the procedure [20]. Normal saline without epinephrine is the most common solution used for the injection. Normal saline is rapidly absorbed, and a repeated injection may be necessary. Dextrose, hyaluronic acid, glycerol, or other solutions have been used to allow longer-lasting injection, but are generally reserved for a submucosal dissection.