504 Endoscopic Piecemeal Resection of Large Colorectal Adenomas: a Systematic Two-Step Approach to Optimize Outcomes

Endoscopic piecemeal resection (EPMR) of colorectal lesions larger than 30 mm may occasionally require multiple steps and not infrequently end up with standard surgery. Two-step EPMR, i.e. the completion of the procedure within 4 to 6 weeks, would allow avoidance of excessive manipulation of the severed area thus reducing the risk of complications and, at the same time, facilitate early identification and treatment of adenoma remnants thus reducing the neoplastic recurrence rate. Aim of the study is to evaluate the impact of systematic two-step EPMR on early morbidity and 12-mo outcomes. Patients with sessile polyps or laterally spreading tumours (LST) larger than 30 mm were recruited in a prospective single-center study. EPMR was systematically performed in two scheduled sequential steps. At 1st step as much of the lesion as possible was removed, with obvious intent to complete resection; in the 2nd step, carried out 4 to 6 wks later, the procedure was completed. At this stage, magnified inspection of the resection area provided clues to simple biopsy (scar tissue devoid of any pattern) or further resection ± APC (adenoma remnants). Endoscopic follow-up was scheduled at 6 and 12 months after this second step (time zero). Over a period of 19 months, a total of 54 patients were included (35 males, mean age 66.8 years, age range 27-82). There were 23 sessile polyps - mean size 42 (range 30-55) mm and 31 LSTs - mean size 49 (range 30-75) mm. Sessile lesions were located in the rectosigmoid (17) and proximal colon (6), whereas LSTs were located in the proximal colon (13), left colon (5) and rectum (13). The standard ER technique by submucosal injection and snare resection was always employed. Intra-procedural bleeding was recorded in 7 instances, all successfully controlled by thermal therapy or clips. No delayed bleeding or perforation occurred. There was no procedure-related mortality. Final histology of the resected lesions was low-grade adenoma (4 sessile and 17 LST), high grade adenoma or mucosal cancer (19 sessile and 13 LST) and submucosal carcinoma (1 G-mixed LST). Retreatment was deemed necessary in 19/54 pts during the second step. See table for 12-months outcomes.Two-step EPMR of colorectal lesions ≥ 30 mm is safe and allows completion of the procedure at a later stage without jeopardizing positive long-term outcomes. This approach may potentially reduce the rate of “recurrent” adenoma by early inspection and retreatment of any residual tissue. Tabled 1 Follow-up Scheduled retreatment Residual or recurrent adenoma 4-6 weeks (2° step) 19/54 — 6 months ⁎ from the end of the procedure (time zero after second step) — 8/54 (14.8%) 12 months ⁎ from the end of the procedure (time zero after second step) — 4/53 (7.5%) from the end of the procedure (time zero after second step) Open table in a new tab