Introduction Rectal polyps extending to the dentate line (RPDL) pose a technical challenge to endoscopic resection due to the narrow lumen, rich venous/haemorrhoidal plexus and proximity to the skin. Conventional snare EMR is challenging due to the restrcited space and lack of precision with the snare. This has led to the use of surgical techniques like TEMS and TAR for resection of RPDLs. Knife Assisted snare Resection (KAR) allows for precise mucosal incision at the dentate line and the dissection of the polyp from the anorectal junction. We aim to assess the feasibility, safety and efficacy of KAR for RPDLs.

Methods This is a prospective observational study of patients who underwent KAR with a mean follow up of 32 months (range 1–83 months). All procedures were done on a day case basis and were carried out under sedation by two endoscopists using high definition gastroscopes with a distal transparent cap. The polyp margin on the anal side was injected with lifting solution consisting of gelofusin, indigo carmine, 1% lignocaine and adrenaline. Haemostasis was maintained using a combination of the endoscopic knife and coag-grasper (Olympus Medical). A mucosal incision was extended around the margins of the polyp, followed by submucosal dissection to facilitate snare deployment to achieve complete polyp resection. Post-procedural antibiotics were not routinely given.

Results A total of forty patients (20 female, median age 69 years) underwent KAR for RPDLs over the study period. The polyp characteristics and histology are described in Table 1. The curative resection after a single KAR was achieved in 33 (82.5%) patients. 7 of the 40 patients required further KARs, leading to a total curative resection rate to 97%. The risk factors for multiple resections are polyps measuring >60 mm and encompassing >50% of the circumference (p < 0.01). Overall, there was one complication where the patient had delayed bleeding which was managed conservatively. None of the patients experienced perforation, or post-procedural sepsis.

Conclusion This is the largest reported series of KAR for RPDLs. Our data demonstrates that for Western endoscopists, KAR is a very safe and effective technique in the treatment of RPDLs. As KAR is a viable alternative to full ESD, TEMS and TAR, it will play an increasingly significant role in the management of RPDLs.

Disclosure of Interest None Declared