Autologous Fecal Microbiota Transplantation for Anal Function Recovery After Ileostomy Reversal in Rectal Cancer

Autologous Fecal Microbiota Transplantation for Anal Function Recovery After Ileostomy Reversal in Patients With Rectal Cancer: A Prospective, Single-center, Single-arm, Open-label Clinical Study

This prospective, single-center, single-arm, open-label clinical study aims to evaluate whether autologous fecal microbiota transplantation can improve bowel and anal function after ileostomy reversal in patients with rectal cancer who underwent radical rectal cancer surgery with protective loop ileostomy. Eligible patients will receive autologous fecal microbiota transplantation before ileostomy reversal. The primary outcome is the Low Anterior Resection Syndrome score at 3 months after ileostomy reversal. Secondary outcomes include fecal incontinence score, colonoscopic findings before ileostomy reversal, gut microbiota profiles, inflammatory markers, anorectal manometry, pelvic floor electromyography, and safety outcomes.

Study Overview

• Status: Active, not recruiting
• Conditions: Low Anterior Resection Syndrome; Rectal Cancer; Fecal Incontinence; Ileostomy; Gut Microbiota Dysbiosis; Diversion Colitis
• Intervention / Treatment: Biological: Autologous Fecal Microbiota Transplantation

Detailed Description

Patients with rectal cancer who undergo radical resection with protective loop ileostomy may experience diversion-related changes in the distal bowel, gut microbiota dysbiosis, diversion colitis, and impaired bowel function after ileostomy reversal. Autologous fecal microbiota transplantation may help restore the intestinal microbial environment in the defunctioned bowel and improve postoperative bowel function.

In this study, eligible patients will undergo standard radical rectal cancer surgery with protective loop ileostomy. At approximately 8 weeks after surgery, patients without severe postoperative complications such as anastomotic leakage will undergo anal swab sampling for 16S rRNA gene sequencing. Autologous fecal microbiota transplantation will be performed once weekly at postoperative weeks 8, 9, 10, and 11. At approximately 12 weeks after surgery, colonoscopy will be performed to evaluate the distal bowel mucosa, and intestinal secretion samples will be collected for 16S rRNA gene sequencing. Ileostomy reversal will then be performed according to routine clinical practice. Bowel function will be followed for 3 months after ileostomy reversal, with the primary endpoint being the LARS score at 3 months after reversal.

• Study Type: Interventional
• Enrollment (Actual): 35
• Phase: Not Applicable

Contacts and Locations

Study Locations

• China
  • Beijing Municipality
    • Beijing, Beijing Municipality, China, 100044
      • Peking University People's Hospital

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Age 18 to 75 years.
2. Histologically or clinically confirmed rectal cancer with the lower tumor margin less than 12 cm from the anal verge.
3. Undergoing radical rectal cancer surgery with protective loop ileostomy.
4. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
5. Able to understand the study procedures and willing to provide written informed consent.

Exclusion Criteria:

1. History of inflammatory bowel disease, bacterial colitis, or other preoperative colonic inflammatory disease.
2. Requirement for emergency surgery due to intestinal obstruction, perforation, bleeding, or other emergency conditions.
3. Pregnant or lactating women.
4. Presence of clinically significant gut microbiota dysbiosis before enrollment, as judged by the investigator.
5. Planned postoperative radiotherapy, chemotherapy, or chemoradiotherapy.
6. Poor compliance, inability to tolerate the intervention, or judged by the investigator to be unsuitable for participation in this clinical study.
7. Severe postoperative complications such as anastomotic leakage.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Autologous Fecal Microbiota Transplantation Group; Participants with rectal cancer who underwent radical rectal cancer surgery with protective loop ileostomy will receive autologous fecal microbiota transplantation before ileostomy reversal.

Biological: Autologous Fecal Microbiota Transplantation; Autologous fecal microbiota transplantation will be prepared from the participant's own fecal material collected from the ileostomy output. Approximately 50 g of fecal material will be mixed with 100 mL sterile normal saline, homogenized, filtered through sterile sieves, and administered slowly into the distal bowel via transanal catheter/enema. The procedure will be performed once weekly at postoperative weeks 8, 9, 10, and 11, for a total of four administrations. Participants will be observed after the procedure according to the study protocol.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Low Anterior Resection Syndrome Score at 3 Months After Ileostomy Reversal	Low Anterior Resection Syndrome (LARS) score will be assessed using the LARS questionnaire at 3 months after ileostomy reversal. The total score ranges from 0 to 42 points, with higher scores indicating more severe bowel dysfunction. Scores of 0-20 indicate no LARS, 21-29 indicate minor LARS, and 30-42 indicate major LARS.	3 months after ileostomy reversal

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Colonoscopic Mucosal Findings Before Ileostomy Reversal	The distal bowel mucosa will be evaluated by colonoscopy before ileostomy reversal. Findings related to diversion colitis, including mucosal erythema, edema, friability, erosion, ulceration, bleeding, and mucus retention, will be recorded.	Approximately 12 weeks after initial surgery and before ileostomy reversal

Collaborators and Investigators

• Sponsor: Peking University People's Hospital

Study record dates

Study Major Dates

• Study Start (Actual): March 25, 2025
• Primary Completion (Actual): May 20, 2026
• Study Completion (Estimated): September 1, 2026

Study Registration Dates

• First Submitted: July 14, 2026
• First Submitted That Met QC Criteria: July 14, 2026
• First Posted (Actual): July 17, 2026

Study Record Updates

• Last Update Posted (Actual): July 17, 2026
• Last Update Submitted That Met QC Criteria: July 14, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: rectal cancer; low anterior resection syndrome; gut microbiota; bowel function; anal function; LARS score; 16S rRNA sequencing; ileostomy reversal; autologous fecal microbiota transplantation; diversion colitis
• Additional Relevant MeSH Terms: Postoperative Complications; Pathologic Processes; Neoplasms by Site; Neoplasms; Intestinal Diseases; Gastrointestinal Neoplasms; Digestive System Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Colorectal Neoplasms; Intestinal Neoplasms; Rectal Diseases; Colonic Diseases; Pathological Conditions, Signs and Symptoms; Low Anterior Resection Syndrome; Rectal Neoplasms; Fecal Incontinence
• Other Study ID Numbers: PKUPH-FMT-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared. The study is a single-center clinical study with a relatively small sample size and includes sensitive clinical information, surgical details, functional outcomes, and microbiome sequencing data. Even after de-identification, there may remain a potential risk of participant re-identification. In addition, the informed consent form did not include specific permission for public sharing of individual-level participant data. Aggregate study results will be reported in publications or presentations.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No