Clinical outcomes of colorectal endoscopic submucosal dissection and risk factors associated with piecemeal resection.

BACKGROUND/AIMS: We aimed to investigate the factors associated with piecemeal resection of colorectal neoplasia (CRN), in spite of endoscopic submucosal dissection (ESD). MATERIALS AND METHODS: We analyzed the retrospective data for colorectal ESD cases from January 2005 to April 2014. We also reviewed the piecemeal endoscopic mucosal resection (EMR) for CRNs ≥20 mm, performed over the same period. RESULTS: En bloc resection was possible in 648 (85.7%) of 756 lesions in 740 patients. Multivariate analysis showed that hybrid ESD (odds ratio (OR), 29.07; 95% confidence interval (CI), 15.46-54.65; p<0.01) and mild or severe submucosal fibrosis (OR, 3.62; 95% CI, 1.94-6.76; p<0.01) were independently associated with piecemeal ESD. The en bloc ESD group showed higher histologic complete resection rate than the piecemeal ESD group (80.4% vs. 56.5%; p<0.01), and the piecemeal ESD group showed higher recurrence rate than in the en bloc ESD group (5.6% [4/72] vs. 0.7% [3/450]; p<0.01). Overall recurrence rate was 1.3% (7/522). CONCLUSION: Hybrid ESD and submucosal fibrosis are independently associated with piecemeal ESD. Piecemeal ESD cases recurred more frequently than en bloc ESD cases.