EPOC trial

The EPOC trial (Prophylactic clip closure after ESD of large flat and sessile polyps) is a multicenter randomized controlled trial conducted to evaluate the effectiveness of prophylactic clip closure in reducing delayed bleeding rates following colorectal endoscopic submucosal dissection (ESD) of flat and sessile polyps measuring 20–50 mm. The trial was conducted across four institutions in Japan and aimed to address the lack of evidence regarding the efficacy of clip closure in colorectal ESD, as opposed to endoscopic mucosal resection (EMR), where its benefits are better established.

Key Details of the EPOC Trial:

Objective:

To compare the clinically significant delayed bleeding rates between a prophylactic clip closure group and a control group following ESD for colorectal polyps.

Design:

• Multicenter randomized controlled trial.
• Patients were randomly assigned to two groups:
• Closure group: Underwent prophylactic clip closure after ESD.
• Control group: Did not receive clip closure after ESD.
• The trial included both intention-to-treat (ITT) and per-protocol (PP) analyses.

Primary Endpoint:

The delayed bleeding rate after colorectal ESD.

Secondary Endpoints:

• Severe delayed bleeding rates.
• Delayed perforation rates.
• Post-ESD coagulation syndrome rates.

Results:

1. Delayed Bleeding Rates:

• ITT analysis showed delayed bleeding rates of 6.7% in the closure group and 20.1% in the control group.
• The absolute risk difference (ARD) for delayed bleeding was 13.5% (95% CI: 5.6% to 20.9%), with an odds ratio (OR) of 0.28 (95% CI: 0.13 to 0.60; p<0.001).

2. Severe Delayed Bleeding Rates:

• Severe delayed bleeding rates were 1.3% in the closure group and 8.7% in the control group.
• ARD was 7.4% (95% CI: 2.2% to 12.4%), with an OR of 0.14 (95% CI: 0.03 to 0.64; p=0.003).

3. Multivariate Analysis:

• Prophylactic clip closure was identified as a significant independent preventive factor for both delayed bleeding (OR: 0.22; 95% CI: 0.08 to 0.50; p<0.001) and severe delayed bleeding (OR: 0.22; 95% CI: 0.05 to 0.76; p=0.015).

4. Other Findings:

• No cases of delayed perforation were observed.
• Post-ESD coagulation syndrome rates were not significantly different between the closure and control groups.
• Clip closure was successfully achieved in approximately 90% of cases.

Conclusion:

Prophylactic clip closure significantly reduced delayed bleeding rates following colorectal ESD for polyps measuring 20–50 mm. It was recommended as a preventive measure to improve safety outcomes in colorectal ESD procedures.

Implications for Practice and Policy:

The study supports the adoption of prophylactic clip closure as a standard practice after colorectal ESD to mitigate the risk of delayed bleeding, which is a common and serious complication.