Risk Factors, Clinical Course, and Management of Delayed Perforation After Colorectal Endoscopic Submucosal Dissection: A Large-Scale Multicenter Study

INTRODUCTION: Delayed perforation (DP) remains a significant complication of colorectal endoscopic submucosal dissection (ESD). This study analyzed the risk factors, clinical course, and management for DP following colorectal ESD. METHODS: We retrospectively reviewed 4,632 consecutive colorectal ESD cases from 13 institutions between January 2006 and May 2024. DP cases were identified, and the incidence rate, along with patient/lesion characteristics (as tumor size, location, and severe fibrosis) were assessed. The clinical course, including onset timing, initial treatments, need for surgery, and risk factors were examined. RESULTS: DP occurred in 18 cases, with an incidence rate of 0.39% [95% confidence interval (CI): 0.24-0.62]. The mean tumor size was 49.7 ± 35.7 mm. The rates of right-sided colon lesions and severe fibrosis were observed in 77.8 and 61.2%, respectively. DP occurred on post-procedure day 1 in 55.8% of cases, day 2 in 22.2%, and on day 3 or later in 22.2%. Initial DP management included conservative treatment in five cases (27.8%), endoscopic closure in six (33.3%), and surgery in seven cases (38.9%). Among the six cases managed endoscopically, five (83.3%) were successfully managed without surgery. Finally, surgery was required in 11 cases (61.1%). Multivariate analysis (odds ratio [95%CI]) identified severe fibrosis (4.61 [1.50-14.20], p = 0.007), and long procedure time (1.01 [1.00-1.02], p = 0.042), as significant risk factors for DP, while complete closure was inversely correlated with DP risk (0.12 [0.01-0.96], p = 0.046). CONCLUSIONS: This study identified DP incidence and risk factors after colorectal ESD, with some cases requiring surgery. Endoscopic treatment may prevent surgery.