Introduction Low rectal polyps are challenging to resect. We aim to compare safety, feasibility and outcomes of endoscopic resection of low rectal polyps (within 5 cm of dentate line) versus mid to high rectal polyps.

Method Cohort study. All patients who had endoscopic resection of rectal polyps >20 mm from 2009 to July 2014 were included. All procedures performed by a single experienced endoscopist. Benign LST-G lesions were resected by conventional EMR technique but polyps close to dentate line, those with scarring, and flat LST-NG lesions were resected either by full ESD or Knife assisted resection technique.

Results 181 polyps resected in 179 patients.

Avg. patient age 71 years.

Mean polyp size 50 mm (20–170 mm). Mean follow up 3 years.

Referrals were due to large polyp size, proximity to dentate line or haemorrhoidal bed, scarring or >50% circumference involvement.

Polyp characteristics: 61/181(33.7%) >50 mm size, 34/181(18.8%) scarred, 109/181(60.2%) in high rectum and 72/181(39.8%) in low rectum.

110/181(60.8%) resected by ESD and 71/181(39.2%) by EMR. 60/181(33.2%) resected en bloc. Histology showed 8(4.4%) cancers and 27(15%) HGD. There was no significant difference between high and low rectal lesions.

Follow up was available for 158. Endoscopic cure rate: 147/158(93%). Of these 124/147(84%) required 1 attempt, 17/147(11.5%) required 2 and 6/147(4.5%) required more than 2 attempts for complete cure. Recurrence/residual polyp after first attempt seen in 30/158 (19%) of patients. Univariate analysis showed that recurrence was significantly linked to size >50 mm, piecemeal resection, low rectal lesions and scarring (Table 1).

The complication rate was 14/181(7.7%) which were all managed conservatively. There was 1(0.5%) significant intraprocedural bleed. There were 7(3.9%) delayed bleeds (2 needing transfusion), 1(0.5%) post polypectomy syndrome and 5(2.7%) cases of exposed muscle fibres clipped during the procedure with no further sequelae.

There were no factors significantly predictive of complications.

Conclusion Rectal polyps referred for resection are generally very large (mean 50 mm).

It is safe and feasible to resect very low rectal polyps around the dentate line. We found no difference in complication rates between low and high rectal polyps. Given large sizes and rectal location, the low cancer rate reflects our careful lesion selection. Recurrence is higher in low rectal polyps and those with large size and scarring. However, repeat attempts can achieve complete clearance.

Disclosure of interest None Declared.