Endoscopic mucosal resection of 161 cases of large sessile or flat colorectal polyps

Objective. Large sessile or flat colorectal polyps, which are traditionally treated surgically, may be amenable to endoscopic mucosal resection (EMR), often using a piecemeal method. Appropriate selection of lesions and a careful technique may enhance the efficacy of EMR for polyps >= 20 mm in diameter without compromising safety. The aim of this study was to identify the factors that may be predictive of the risk of polyp recurrence. Material and methods. A retrospective analysis was conducted on the outcome of 161 polyps >= 20 mm in diameter, treated by piecemeal EMR at a single centre using the "lift and cut'' technique. All records were reviewed for polyp size, site, morphology and histology. Polypectomy technique, patient follow- up, polyp recurrence and surgical interventions were also recorded. Results. Over an 8- year period, 161 colonic polyps measuring >= 20 mm were removed by EMR. Follow- up data were available for 149 cases (93%) with a mean polyp diameter of 32.5 mm; the total success rate of endoscopic polyp removal was 95.4%. The number of cases requiring 1, 2, 3, 4 and 6 attempts at EMR was 89 (60%), 36 (24%), 14 (9%), 2 (1.3%) and 1 (0.7%), respectively. Recurrence was significantly related to polyp size (p< 0.001). There was no statistically significant relationship between site and recurrence. Seven patients (4.6%) underwent surgical intervention after EMR because of failed clearance. There were no post- EMR perforations and significant bleeding was reported in only two patients (1.7%). Conclusions. With careful attention to technique, piecemeal EMR is a safe option for the resection of most sessile and flat colorectal polyps >= 20 mm in size. A stricter follow- up may be required for larger lesions because of a higher risk of recurrence.