Endoscopic resection of large sessile colorectal polyps using a submucosal saline injection technique

Endoscopic removal of sessile colorectal polyps 2 cm or greater in diameter is very difficult. We evaluated the safety and usefulness of submucosal saline injection in endoscopic resection of these polyps.

Under colonoscopic observation, 0.9% NaCl was injected submucosally through needle forceps to elevate polyps, which were then resected by electrocoagulation. Before 1989, the depth and healing status of ulcers produced by endoscopic resection with (N = 12) and without (N = 16) submucosal saline injection were examined in specimens obtained at subsequent colectomies. Between 1990 and 1993, patients were assigned by weighted randomization to undergo colonoscopic polypectomy with (N = 24) or without (N = 5) submucosal saline injection.

All 12 ulcers after submucosal saline injection were confined to the submucosal layer while 7 (44%) of 16 ulcers without submucosal saline injection reached the muscle layer or deeper. Seventeen of 24 (71%) polyps were completely removed (14 piecemeal and 3 en bloc) without serious complications after saline injection. Resection without submucosal saline injection was complete, but piecemeal, for two of five polyps; postresection bleeding occurred in one case.

Endoscopic resection after submucosal saline injection is a safe and effective treatment for large, sessile colorectal polyps.