Low-Residue Diet Versus Rectal Enema Before Laparoscopic Surgery for Endometrial Cancer

Low-Residue Diet Versus Rectal Enema Before Laparoscopic Endometrial Cancer Surgery: A Prospective Randomized Controlled Trial

The goal of this clinical trial is to compare a standardized 3-day bowel preparation protocol with a rectal enema before laparoscopic surgery for endometrial cancer. The study will evaluate whether the dietary bowel preparation protocol can be used instead of a rectal enema while maintaining an adequate surgical view during surgery.

The main questions it aims to answer are:

• Can the dietary bowel preparation protocol provide surgical exposure comparable to a rectal enema?
• Can the dietary bowel preparation protocol reduce the minimum Trendelenburg position and pneumoperitoneum pressure required to obtain an adequate surgical view?
• Does either bowel preparation method cause more discomfort or side effects before surgery?

Researchers will compare a standardized 3-day bowel preparation protocol with a rectal enema before surgery.

Participants will:

• Be randomly assigned to receive either a standardized 3-day bowel preparation protocol or a rectal enema before surgery.
• Undergo standard laparoscopic surgery for endometrial cancer.
• Have surgical exposure, the minimum Trendelenburg position, the minimum pneumoperitoneum pressure, operative outcomes, postoperative recovery, and bowel preparation-related symptoms and discomfort assessed as part of routine clinical care.

Study Overview

• Status: Not yet recruiting
• Conditions: Endometrial Cancer
• Intervention / Treatment: Behavioral: Low-Residue Diet; Drug: Sodium Phosphate Rectal Enema

Detailed Description

Adequate bowel preparation is important for achieving optimal surgical exposure during laparoscopic surgery for endometrial cancer. Inadequate bowel preparation may impair visualization of the operative field, requiring steeper Trendelenburg positioning and higher pneumoperitoneum pressures, which may increase the physiological burden of surgery and affect operative performance.

Mechanical bowel preparation with rectal enema is commonly used before gynecologic surgery, although its routine use remains controversial because evidence supporting its clinical benefit is limited. A standardized 3-day bowel preparation protocol may improve patient tolerance while maintaining adequate surgical conditions. However, prospective randomized studies comparing these two approaches specifically in laparoscopic endometrial cancer surgery remain limited.

This prospective randomized controlled trial will compare a standardized 3-day bowel preparation protocol with a preoperative rectal enema before laparoscopic surgery for endometrial cancer. The primary objective is to determine whether the dietary bowel preparation protocol can provide surgical conditions comparable to those achieved with rectal enema.

In addition to subjective assessment of surgical exposure, the study will evaluate objective intraoperative parameters, including the minimum Trendelenburg position and the minimum pneumoperitoneum pressure required to maintain an adequate surgical view. Operative outcomes, postoperative recovery, patient tolerance of the bowel preparation methods, and bowel preparation-related symptoms will also be evaluated.

The findings of this study may help optimize preoperative bowel preparation strategies, reduce unnecessary patient burden, and support evidence-based perioperative care for patients undergoing laparoscopic surgery for endometrial cancer.

• Study Type: Interventional
• Enrollment (Estimated): 100
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Mahmut Yassa, MD; Phone Number: +90 539 663 54 84; Email: mahmut_yassa@hotmail.com

Study Locations

• Turkey (Türkiye)
  • Istanbul, Turkey (Türkiye)
    • Basaksehir Cam and Sakura City Hospital

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Female participants aged 18 to 90 years.
• Scheduled to undergo elective laparoscopic surgery for endometrial cancer.
• Willing and able to provide written informed consent.

Exclusion Criteria:

• Planned open (abdominal) surgery.
• Known allergy or contraindication to sodium phosphate rectal enema.
• Age over 90 years.
• Refusal or inability to provide written informed consent.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Low-Residue Diet; Participants will follow a standardized 3-day bowel preparation protocol before surgery. The protocol includes a low-residue diet on day 3 before surgery, a soft or pureed diet on day 2, and a clear liquid diet on the day before surgery	Behavioral: Low-Residue Diet; Participants will follow a standardized 3-day bowel preparation protocol consisting of a low-residue diet on day 3 before surgery, a soft or pureed diet on day 2, and a clear liquid diet on the day before surgery, with adequate hydration throughout the preparation period.
Active Comparator: Rectal Enema; Participants will receive a single sodium phosphate rectal enema approximately 12 hours before surgery according to the institutional bowel preparation protocol	Drug: Sodium Phosphate Rectal Enema; Participants will receive a single sodium phosphate rectal enema approximately 12 hours before surgery according to the manufacturer's instructions and the institutional bowel preparation protocol.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intraoperative Visual Index Score	Surgical exposure will be assessed intraoperatively using the Visual Index score after establishment of pneumoperitoneum and placement of the camera trocar and one lateral ancillary trocar. The score ranges from 0 to 2, where 0 indicates inadequate visualization despite bowel retraction with one grasper, 1 indicates adequate visualization requiring bowel retraction with one grasper, and 2 indicates adequate visualization without bowel retraction. Higher scores indicate better surgical exposure.	Intraoperatively, after pneumoperitoneum establishment and placement of the camera trocar and one lateral ancillary trocar
Minimum Trendelenburg Position Required for Adequate Surgical Exposure	The minimum Trendelenburg angle (degrees) required to achieve adequate visualization of the pelvis will be recorded intraoperatively using the predefined assessment protocol.	Intraoperatively
Minimum Pneumoperitoneum Pressure Required for Adequate Surgical Exposure	The minimum pneumoperitoneum pressure (mmHg) required to achieve adequate visualization of the pelvis will be recorded intraoperatively using the predefined assessment protocol.	Intraoperatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Operative Time	Total operative time measured from skin incision to skin closure, recorded in minutes.	During surgery
Length of Hospital Stay	Length of postoperative hospital stay, measured in days from surgery until hospital discharge.	At hospital discharge, assessed up to 30 days after surgery
Time to First Flatus	Time from completion of surgery to the first documented passage of flatus, measured in hours. The occurrence and timing of first flatus will be assessed during daily postoperative visits until the event occurs or until hospital discharge.	From completion of surgery until the first documented passage of flatus, assessed up to 7 postoperative days
Patient Tolerance of Bowel Preparation	Patient tolerance will be assessed using completion of the assigned bowel preparation protocol, willingness to repeat the same preparation method in a future surgery, postoperative pain score, and bowel preparation-related symptoms. Symptoms will include nausea, overall discomfort, headache, insomnia, thirst, abdominal cramps, weakness, and fatigue, each assessed using a 0-10 numeric rating scale, where 0 indicates no symptom and 10 indicates the worst possible symptom.	From preoperative bowel preparation until postoperative day 1

Collaborators and Investigators

• Sponsor: Mahmut Yassa
• Investigators: Principal Investigator: Mahmut Yassa, MD, Başakşehir Çam & Sakura City Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): July 15, 2026
• Primary Completion (Estimated): January 15, 2028
• Study Completion (Estimated): March 1, 2028

Study Registration Dates

• First Submitted: July 6, 2026
• First Submitted That Met QC Criteria: July 13, 2026
• First Posted (Actual): July 14, 2026

Study Record Updates

• Last Update Posted (Actual): July 14, 2026
• Last Update Submitted That Met QC Criteria: July 13, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Pneumoperitoneum; endometrial cancer; Surgical Exposure; Laparoscopic Surgery; Bowel Preparation; Gynecologic Oncology; Trendelenburg Position; Low-Residue Diet; Rectal Enema
• Additional Relevant MeSH Terms: Urogenital Diseases; Genital Diseases; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Digestive System Diseases; Uterine Diseases; Genital Diseases, Female; Genital Neoplasms, Female; Uterine Neoplasms; Peritoneal Diseases; Pneumoperitoneum; Endometrial Neoplasms
• Other Study ID Numbers: ENDO-DIET-RCT-2026

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified individual participant data underlying the published results, together with a data dictionary, will be made available upon reasonable request to the corresponding investigator. Data will be shared only after publication of the primary study results and subject to institutional approval, a scientifically sound research proposal, and execution of a data use agreement. Additional data may be considered on a case-by-case basis at the discretion of the principal investigator.
• IPD Sharing Time Frame: Beginning 6 months after publication of the primary study results and ending 3 years after publication.
• IPD Sharing Access Criteria: Access will be considered for qualified researchers conducting scientifically sound research. Requests must include a research proposal and, where appropriate, a statistical analysis plan. All requests will be reviewed by the principal investigator and approved according to institutional policies. Approved researchers will be required to sign a data use agreement before receiving de-identified data.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

Drug and device information, study documents

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