Efficacy and Safety of Colorectal Anastomotic Leak Testing

A Comparative Study of Clinical Outcomes Between Leak Testing and No Leak Testing for Anastomosis in Colorectal Cancer Surgery: a Multicenter, Stratified Randomized Controlled Trial.

To evaluate the effectiveness of the gastroscopy, air, and methylene blue (GAM) leak testing in reducing the incidence of postoperative anastomotic complications, especially anastomotic leakage, in patients with colorectal cancer. The primary outcomes included is the incidence of anastomotic complications (mainly anastomotic leak) within 30 days after surgery

Study Overview

• Status: Recruiting
• Conditions: Colorectal Cancer; Colorectal Surgery; Complications; Anastomotic Leakage; Leakage Testing
• Intervention / Treatment: Procedure: Intraoperative leak testing

• Study Type: Interventional
• Enrollment (Estimated): 264
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Yunhong Tian, doctor; Phone Number: 13508087719; Email: drtianyunhong@126.com

Study Locations

• China
  • Sichuan
    • Nanchong, Sichuan, China
      • Recruiting
      • Nanchong Central Hospital
      • Contact: Phone Number: 13508087719; Email: drtianyunhong@126.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Patients diagnosed with colorectal cancer by pathology and scheduled for surgical treatment who meet the surgical indications.
2. Aged between 18 and 85 years.
3. American Society of Anesthesiologists (ASA) physical status classification is I - III.
4. The patient or his/her legal representative can understand and sign the informed consent form and is willing to cooperate throughout the study process.

Exclusion Criteria:

1. Patients with preoperatively diagnosed anastomotic leak or other severe abdominal infections.
2. Patients with severe cardiovascular and cerebrovascular diseases (such as recent myocardial infarction, unstable angina pectoris, severe heart failure, acute cerebral infarction, etc.) who cannot tolerate surgery and related tests.
3. Patients with severely impaired liver and kidney function (liver function Child - Pugh classification C or above, creatinine clearance rate < 30 ml/min).
4. Patients with coagulation disorders (such as platelet count < 50×10⁹/L, international normalized ratio (INR) > 1.5, etc.) that cannot be corrected or are receiving anticoagulant therapy that cannot be adjusted.
5. Patients with a history of abdominal radiotherapy or multiple abdominal surgeries and severe abdominal adhesions that may affect the operation and detection procedures.
6. Patients with other malignant tumors who are receiving active anti-tumor treatment such as radiotherapy and chemotherapy.
7. Patients with mental illness or cognitive impairment who cannot cooperate with the study process and follow-up.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

8

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: ≤5cm Rectal, Pre-chemo, Leak Test; Patients with rectal cancer ≤ 5 cm from the anus, received preoperative chemotherapy and intraoperative leak testing.	Procedure: Intraoperative leak testing; ◦After anastomosis was completed, the integrity of anastomosis was tested intraoperatively. The methods include directly observing the integrity of the anastomosis under gastroscopy, immersing the anastomosis in 500 - 1000 mL of warm saline and temporarily occluding the distal end, filling the anastomotic bowel with air, and injecting 60 mL of methylene blue through colonoscopy. Wrapping a white gauze pad around the anastomosis and observing for methylene blue leakage.
No Intervention: ≤5cm Rectal, Pre-chemo, No Leak Test; Patients with rectal cancer ≤ 5 cm from the anus, received preoperative chemotherapy, and had no intraoperative leak testing.
Experimental: ≤5cm Rectal, No pre-chemo, Leak Test; Patients with rectal cancer ≤ 5 cm from the anus, didn't receive preoperative chemotherapy, and underwent intraoperative leak testing.	Procedure: Intraoperative leak testing; ◦After anastomosis was completed, the integrity of anastomosis was tested intraoperatively. The methods include directly observing the integrity of the anastomosis under gastroscopy, immersing the anastomosis in 500 - 1000 mL of warm saline and temporarily occluding the distal end, filling the anastomotic bowel with air, and injecting 60 mL of methylene blue through colonoscopy. Wrapping a white gauze pad around the anastomosis and observing for methylene blue leakage.
No Intervention: ≤5cm Rectal, No pre-chemo, No Leak Test; Patients with rectal cancer ≤ 5 cm from the anus, didn't receive preoperative chemotherapy, and had no intraoperative leak testing.
Experimental: >5cm Colorectal, Pre-chemo, Leak Test; Patients with colorectal cancer > 5 cm from the anus, received preoperative chemotherapy, and underwent intraoperative leak testing.	Procedure: Intraoperative leak testing; ◦After anastomosis was completed, the integrity of anastomosis was tested intraoperatively. The methods include directly observing the integrity of the anastomosis under gastroscopy, immersing the anastomosis in 500 - 1000 mL of warm saline and temporarily occluding the distal end, filling the anastomotic bowel with air, and injecting 60 mL of methylene blue through colonoscopy. Wrapping a white gauze pad around the anastomosis and observing for methylene blue leakage.
No Intervention: >5cm Colorectal, Pre-chemo, No Leak Test; Patients with colorectal cancer > 5 cm from the anus, received preoperative chemotherapy, and had no intraoperative leak testing.
Experimental: >5cm Colorectal, No pre-chemo, Leak Test; Patients with colorectal cancer > 5 cm from the anus, didn't receive preoperative chemotherapy, and underwent intraoperative leak testing.	Procedure: Intraoperative leak testing; ◦After anastomosis was completed, the integrity of anastomosis was tested intraoperatively. The methods include directly observing the integrity of the anastomosis under gastroscopy, immersing the anastomosis in 500 - 1000 mL of warm saline and temporarily occluding the distal end, filling the anastomotic bowel with air, and injecting 60 mL of methylene blue through colonoscopy. Wrapping a white gauze pad around the anastomosis and observing for methylene blue leakage.
No Intervention: >5cm Colorectal, No pre-chemo, No Leak Test; Patients with colorectal cancer > 5 cm from the anus, didn't receive preoperative chemotherapy, and had no intraoperative leak testing.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants with Anastomotic Leak within 30 days	Count the number of participants who develop anastomotic leak within 30 days after colorectal cancer surgery.	30 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants with Postoperative Complications within 30 days	Count the number of participants who develop postoperative bleeding, anastomotic stenosis, and intra-abdominal infection within 30 days after colorectal cancer surgery.	30 days

Collaborators and Investigators

• Sponsor: Nanchong Central Hospital

Study record dates

Study Major Dates

• Study Start (Actual): December 22, 2024
• Primary Completion (Estimated): January 31, 2029
• Study Completion (Estimated): April 1, 2029

Study Registration Dates

• First Submitted: March 6, 2025
• First Submitted That Met QC Criteria: March 6, 2025
• First Posted (Actual): March 10, 2025

Study Record Updates

• Last Update Posted (Actual): March 31, 2026
• Last Update Submitted That Met QC Criteria: March 29, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Postoperative Complications; Pathologic Processes; Neoplasms by Site; Neoplasms; Intestinal Diseases; Gastrointestinal Neoplasms; Digestive System Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Intestinal Neoplasms; Rectal Diseases; Colonic Diseases; Pathological Conditions, Signs and Symptoms; Colorectal Neoplasms; Anastomotic Leak
• Other Study ID Numbers: 2025008

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No