Comparing the Efficacy of TU-LESS and vNOTES for Hysterectomy of Enlarged Uterus

Protocol for a Comparative Study of the Efficacy of Transumbilical Laparoendoscopic Single-site Surgery (TU-LESS) and Transvaginal Natural Orifice Transluminal Endoscopic Surgery (vNOTES) in Hysterectomy Performed on Patients With Enlarged Uterus: A Prospective Single-blinded, Randomized Clinical Trial

Enlarged uterus is frequently encountered in clinical practice, and its incidence due to conditions such as adenomyosis, uterine fibroids, and other gynecological disorders has steadily increased over the years statistically. For example, greater healthcare awareness has led to more frequent early diagnoses of these conditions, contributing to the observed rise in incidence. Additionally, increasing life expectancy results in more women reaching the perimenopausal and postmenopausal stages, during which conditions like uterine fibroids and adenomyosis become more prevalent. For these women, hysterectomy (removal of the entire uterus) is often the recommended option of treatment.

With advances in surgical techniques over recent decades, there has been a notable shift from traditional open abdominal surgeries to minimally invasive approaches. Laparoscopic surgery has been widely adopted, significantly reducing the size and number of incisions required, thereby promoting faster recovery, minimizing postoperative pain, and reducing the risk of complications.

However, conventional multi-port laparoscopic hysterectomy still presents certain challenges, such as large uterus extraction following resection, and concerns about healing of incisions. In contrast, innovative techniques like Transumbilical Laparoendoscopic Single-Site Surgery(TU-LESS) and Transvaginal Natural Orifice Transluminal Endoscopic Surgery(vNOTES) both take advantage of natural anatomical openings to achieve minimal or no visible scarring. Studies demonstrate that these techniques provide superior outcomes in terms of reduced pain, faster recovery, and quicker return to daily activities compared to traditional multi-port laparoscopic approaches.

Yet a direct comparison of the efficacy of these two methods in real-world, particularly for enlarged uterus, remains inconclusive. Thus this study aims to evaluate and compare the outcomes of these two techniques in patients with enlarged uteri. Participants will be randomly assigned to receive one of the two surgical approaches, ensuring an unbiased comparison of the efficacy of the procedures in terms of healing status and recovery time.

Study Overview

• Status: Not yet recruiting
• Conditions: Adenomyosis; Enlarged Uterus; Uterine Fibroids (UF)
• Intervention / Treatment: Procedure: TU-LESS; Procedure: vNOTES

Detailed Description

Enlarged uterus, mainly caused by adenomyosis, is often associated with symptoms like compression of intestines and urethra(presenting as constipation, urinary frequency, and urgency), dysmenorrhea, menstrual irregularity, and anemia due to menorrhagia. A hysterectomy (removal of the uterus) is often recommended, especially in cases where conservative management like medical treatment fails.

Among all the methods of hysterectomy, TU-LESS and vNOTES are noted for minimized invasiveness and fast recovery. As vNOTES is performed through the vagina and TU-LESS involves a single incision through the umbilicus, they both utilize natural anatomical openings, resulting in minimal to no visible scarring.

• Study Type: Interventional
• Enrollment (Estimated): 210
• Phase: Not Applicable

Contacts and Locations

Study Locations

• China
  • Sichuan
    • Chengdu, Sichuan, China, 610041
      • West China Second University Hospital
      • Contact: Hongyu Jin, MD; Phone Number: 02885244323; Email: jinhongyu324@icloud.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Eligible women aged 18-70 years.
• Women with indications for enlarged uterine volumes who are planning to under go total hysterectomy. Uterine size should exceed that of a 3-month pregnancy (uterine weight ≥ 280 g).
• Patients are willing to be randomly assigned to undergo any of both approaches.
• Patients who are willing to sign the informed consent form.

Exclusion Criteria:

• Individuals who are virgins or have vaginal stenosis.
• Patients requiring concurrent surgical intervention for conditions such as ovarian cysts or lesions of the vulva, vagina, appendix, etc.
• presence of uterus exceeding approximately 20 gestational weeks in size (about 900-1000g), which is beyond the limitations of a single-site laparoscopic approach due to concerns regarding technical feasibility and safety
• Presence of malignancy or strong suspicion of malignancy that may alter the planned surgical approach.
• History of two or more pelvic surgeries or suspected severe pelvic adhesions (rectovaginal examination suggesting rectovaginal endometriosis or limited uterine mobility).
• History of peritoneal dialysis, pelvic radiation therapy and pelvic tuberculosis treated with laparoscopic surgery.
• Patients with prolapse or pelvic inflammation.
• Diabetes mellitus with poor blood glucose control.
• Body mass index greater than 30 kg/m².

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
Active Comparator: TU-LESS for hysterectomy; Patients diagnosed with enlarged uteri following a bimanual examination, with confirmation of the size and nature of the enlargement through imaging techniques such as ultrasound or magnetic resonance imaging (MRI).	Procedure: TU-LESS; patients in TU-LESS group will receive transumbilical laparoendoscopic single-site surgery (TU-LESS) for hysterectomy
Experimental: vNOTES for hysterectomy; Patients diagnosed with enlarged uteri following a bimanual examination, with confirmation of the size and nature of the enlargement through imaging techniques such as ultrasound or magnetic resonance imaging (MRI).	Procedure: vNOTES; patients in vNOTES group will receive transvaginal natural orifice transluminal endoscopic surgery (TU-LESS) for hysterectomy

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
postoperative liquid diet	the proportion of patients able to consume a liquid diet post-surgery	within 24 hours postoperatively
passing flatus	the proportion of patients able to pass flatus	within 24 hours postoperatively
self-urination after catheter removal	The proportion of patients regaining the ability to urinate without assistance after catheter removal	within 24 hours postoperatively
ambulation	The proportion of patients regaining mobility after catheter removal	within 24 hours postoperatively
hospital stay	The percentage of patients discharged within 2 days after surgery	within 2 days postoperatively
examination of pelvic fuction	The assessment of pelvic floor function involves evaluating Stress Urinary Incontinence (SUI), Pelvic Organ Prolapse (POP) and Sexual Dysfunction. The PISQ-IR (Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire) is a validated tool specifically designed to evaluate sexual function in the context of pelvic floor. It is a tool that measures sexual function specifically for women affected by pelvic floor disorders, such as urinary incontinence and pelvic organ prolapse.	within 2 days postoperatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative pain	It is measured by the VAS score. The VAS consists of a 10cm line, with two end points representing 0 ('no pain') and 10 ('pain as bad as it could possibly be').	at 12 hours and 24 hours postoperatively
The duration of operation	It will be measured in min utes, starting from the initiation of the skin (or vag inal) incision and concluding upon the completion of the skin (or vaginal) suturing. If a frozen biopsy is needed during the operation, the increased time for the frozen biopsy should be subtracted. However, pa tients for whom the surgical method is changed due to the result of the frozen biopsy should be excluded.	during operation
amount of bleeding		during operation
Intraoperative complications and postoperative complications	We use the Clavien-Dindo classification to rank a complication in an objective and reproducible manner. It consists of 7 grades (I, II, IIIa, IIIb, IVa, IVb and V). The introduction of the subclasses a and b allows a contraction of the classification into 5 grades (I, II, III, IV and V) depending on the size of the population observed or the of the focus of a study.	within 3 months
abdominal scars assessment	The Patient and Observer Scar Assessment Scale (POSAS) will be used. It consists of two separate scales: the Patient Scale and the Observer Scale and measures scar quality (i.e. how the scar looks and feels) from both perspectives. The observer scores six items: vascularization, pigmentation, thickness, surface roughness, pliability, and surface area. The patient scores six items: pain, pruritus, color, thickness, relief, and pliability. All included items are scored on the same polytomous 10-point scale, in which a score of 1 is given when the scar characteristic is akin to 'normal skin' and a score of 10 reflects the 'worst imaginable scar'. All items are summed to give a total scar score, and therefore, a higher score represents a poorer scar quality.	both at 3 and 6 months after surgery
the total dosage of analgesics taken	also categorized by analgesic type	during the first 24 hours following surgery
The Female Sexual Function Index(FSFI)	Using either a paper sheet or online questionnaire	both at baseline and 6 months after surgery

Collaborators and Investigators

• Sponsor: West China Second University Hospital

Publications and helpful links

General Publications

• Benassi L, Rossi T, Kaihura CT, Ricci L, Bedocchi L, Galanti B, Vadora E. Abdominal or vaginal hysterectomy for enlarged uteri: a randomized clinical trial. Am J Obstet Gynecol. 2002 Dec;187(6):1561-5. doi: 10.1067/mob.2002.127596.
• Zhang W, Deng L, Yang F, Liu J, Chen S, You X, Gou J, Zi D, Li Y, Qi X, Wang Y, Zheng Y. Comparing the efficacy and safety of three surgical approaches for total hysterectomy (TSATH): protocol for a multicentre, single-blind, parallel-group, randomised controlled trial. BMJ Open. 2024 Jan 10;14(1):e074478. doi: 10.1136/bmjopen-2023-074478.

Study record dates

Study Major Dates

• Study Start (Estimated): October 1, 2025
• Primary Completion (Estimated): October 1, 2026
• Study Completion (Estimated): October 1, 2028

Study Registration Dates

• First Submitted: October 19, 2024
• First Submitted That Met QC Criteria: October 27, 2024
• First Posted (Actual): October 29, 2024

Study Record Updates

• Last Update Posted (Estimated): September 18, 2025
• Last Update Submitted That Met QC Criteria: September 16, 2025
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Urogenital Diseases; Genital Diseases; Neoplasms; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Neoplasms by Histologic Type; Uterine Diseases; Genital Diseases, Female; Neoplasms, Connective and Soft Tissue; Neoplasms, Muscle Tissue; Adenomyosis; Leiomyoma
• Other Study ID Numbers: 2020079JHY

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; ICF

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