BACKGROUND AND AIMS
To determine the long-term outcomes after colorectal endoscopic submucosal dissection (ESD), we conducted a large, multicenter, prospective cohort trial with a 5-year observation period.
METHODS
Between February 2013 and January 2015, we enrolled consecutive 1740 patients with 1814 colorectal epithelial neoplasms ≥ 20 mm who underwent ESD. Patients with non-curative resection (non-CR) lesions underwent additional radical surgery as needed. After the initial treatment, intensive 5-year follow-up with planned multiple colonoscopies was conducted to identify metastatic and/or local recurrences. Primary outcomes were overall survival (OS), disease-specific survival (DSS), and intestinal preservation rates. The rates of local recurrence and metachronous invasive cancer were evaluated as the secondary outcomes.
RESULTS
The 5-year OS, DSS, and intestinal preservation rates was 93.6%, 99.6%, and 88.6%, respectively. Patients with CR lesions had no metastatic occurrence, whereas patients with non-CR lesions had 4 metastatic occurrences. Kaplan-Meier curves revealed that OS and DSS rates were significantly higher in patients with CR lesions than in those with non-CR lesions (P>0.001 and P=0.009, respectively). Local recurrence occurred in only eight (0.5%) lesions, which were successfully resected by subsequent endoscopic treatment. Multiple logistic regression analysis revealed that piecemeal resection (hazard ratio [HR] 8.19; 95% confidence interval [CI] 1.47-45.7, P=0.02) and margin-positive resection (HR 8.06; 95% CI 1.76-37.0, P=0.007) were significant independent predictors of local recurrence after colorectal ESD. Fifteen (1.0%) metachronous invasive cancers were identified during surveillance colonoscopy, most of which required surgical resection.
CONCLUSION
A favorable long-term prognosis indicates that ESD can be the standard treatment for large colorectal epithelial neoplasms.