Injection-incision-assisted snare resection of large sessile colorectal polyps

Background: It can be difficult, even for experienced endoscopists, to completely remove large sessile colorectal polyps. We attempted to remove large sessile colorectal polyps without complication and residual tumors. Method: Our new technique is characterized by submucosal pre-injection with a large volume of saline solution and then circumferential incision outside the lesion before resection using a special needle-tipped snare. The mean size of 33 polyps (including 9 elevated sessile, 20 flat nodular [villous], and 4 flat sessile polyps), was 4.0 cm (range, 3.0-8.5 cm). Results: Twenty-five (76%) were resected piecemeal and the remainder as a single specimen. Mild to moderate bleeding occurred in 3 (9.1%), but there was no clinically significant bleeding or perforation. No residual or recurrent tumors were recognized. Invasive carcinoma was revealed most frequently (44%) in elevated sessile polyps; none occurred in flat nodular polyps. Conclusion: Our removal technique appears to be safe and effective. Flat nodular polyps of any size are a particularly good indication for removal by this technique.