Endoscopic (EID) Versus Surgical (TAMIS) Local Excision for Early Stage Rectal Cancer (ENSURE)

September 22, 2026 updated by: Barbara Bastiaansen, Amsterdam UMC, location VUmc

Endoscopic Intermuscular Dissection Versus Transanal Minimally Invasive Surgery for Local Excision of Early Rectal Cancer: a Multicenter Randomized Controlled Trial

In this clinical trial, we compare the endoscopic technique, endoscopic intermuscular dissection (EID), with the surgical technique, transanal minimally invasive surgery (TAMIS) for the treatment of early stage rectal cancer. The aim of this study is to investigate whether one of them leads to better outcomes.

Researchers will focus particularly on:

  • How effectively each technique completely removes the cancer
  • How quickly patients recover after treatment and whether complications occur
  • Outcomes after three years (does the cancer go away, or does it come back?)
  • The impact of both techniques on bowel function and quality of life

Participants will:

  • Be randomly assigned to receive either surgical or endoscopic treatment for their rectal cancer
  • Keep a diary twice a day to record pain symptoms and recovery during the first 30 days after treatment and complete questionnaires within a 3 year period
  • Visit the clinic for follow-up appointments within a 3 year period

Study Overview

Detailed Description

In the Netherlands, more than 3,000 people are diagnosed with rectal cancer each year. Approximately one-third of these patients have early-stage disease (cT1-2N0M0). Due to the low risk of lymph node metastasis, these cancers are potentially suitable for local, organ-preserving treatment. If histological analysis confirms complete removal without high-risk features, major rectal surgery can be avoided. For suspected deep submucosal invasive cancer of the rectum, a local excision (LE) can be performed by gastroenterologists using EID or by surgeons using TAMIS. Although both LE approaches are considered standard treatment for early stage rectal cancer (T1b), they have never been directly compared. This national study aims to compare the efficacy, safety, and cost-effectiveness of these two approaches. Should both techniques prove equally effective at completely removing rectal T1b, EID may offer a less burdensome and more cost-effective treatment option.

Study Type

Interventional

Enrollment (Estimated)

246

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

      • Alkmaar, Netherlands
        • NoordWest Ziekenhuisgroep
        • Contact:
        • Principal Investigator:
          • Mich Dunker, MD PhD
      • Almere Stad, Netherlands
        • Flevoziekenhuis
        • Contact:
        • Principal Investigator:
          • Anthony van de Ven, MD
      • Amersfoort, Netherlands, 3813 TZ
        • Meander Medisch Centrum
        • Contact:
        • Principal Investigator:
          • Esther Consten, MD PhD
      • Amsterdam, Netherlands
        • OLVG
        • Contact:
        • Principal Investigator:
          • Michael Gerhards, MD PhD
      • Amsterdam, Netherlands, 1081 HV
        • Amsterdam UMC
        • Contact:
        • Sub-Investigator:
          • Elena Kasantsidis, MD
        • Principal Investigator:
          • Barbara Bastiaansen, MD
      • Amsterdam, Netherlands
        • Antoni Van Leeuwenhoek
        • Contact:
        • Principal Investigator:
          • Brechtje Grotenhuis, MD PhD
      • Capelle aan den IJssel, Netherlands
        • Ijsselland Ziekenhuis
        • Contact:
        • Principal Investigator:
          • Pascal Doornebosch, MD
      • Deventer, Netherlands
        • Deventer Ziekenhuis
        • Contact:
        • Principal Investigator:
          • Frank ter Borg, MD
      • Eindhoven, Netherlands
        • Catharina Ziekenhuis
        • Contact:
        • Principal Investigator:
          • Ramon Michel Schreuder, MD
      • Groningen, Netherlands, 9713 GZ
        • Universitair Medisch Centrum Groningen
        • Contact:
        • Contact:
        • Principal Investigator:
          • Wouter Nagengast, MD PhD
      • Haarlem, Netherlands
        • Spaarne Gasthuis
      • Hoorn, Netherlands
        • Dijklander Ziekenhuis
        • Contact:
        • Principal Investigator:
          • Joris van den Broek, MD
      • Leiden, Netherlands
        • Leiden Universitair Medisch Centrum
        • Contact:
        • Principal Investigator:
          • Jurjen Boonstra, MD PhD
      • Nieuwegein, Netherlands
        • St. Antonius Ziekenhuis
      • Roermond, Netherlands
        • Laurentius Ziekenhuis
        • Contact:
        • Principal Investigator:
          • Jeroen Leijtens, MD
      • Rotterdam, Netherlands, 3015 GD
        • Erasmus Medisch Centrum
        • Contact:
        • Principal Investigator:
          • Arjun Koch, MD PhD
      • The Hague, Netherlands
        • Haaglanden Medisch Centrum
        • Contact:
        • Principal Investigator:
          • Andreas Marinelli, MD PhD
      • Utrecht, Netherlands, 3584 CX
        • University Medical Center Utrecht
        • Contact:
        • Principal Investigator:
          • Leon Moons, MD PhD
      • Zwolle, Netherlands
        • Isala
        • Contact:
        • Principal Investigator:
          • Erik van Westreenen, MD PhD

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion criteria:

To be eligible to participate in this study, a patient must meet all of the following criteria:

  • Adult patients (≥ 18 years of age).
  • Suspected rectal D-SMIC based on optical diagnosis using narrow-band imaging:
  • Hiroshima C2/3, JNET 3, NICE III, Kudo Vn pit pattern.
  • The presence of non-lifting together with features of superficial submucosal invasion (Hiroshima C1, JNET 2B, Kudo Vi pit pattern).
  • MRI shows cT1-T2 invasion and minimum of 1 mm preserved muscularis propria.
  • Tumour with its lower border situated on or below the level of the sigmoid take off as shown on rectal MRI.
  • Staging rectal MRI confirms absence of suspicious malignant mesorectal lymph nodes, defined as mucinous lymph nodes, perirectal lymph nodes >9 mm in short-axis diameter, or ≥7 mm for lateral lymph nodes (classified as certain cN+), or 5-9 mm peri-rectal lymph nodes with at least 2 suspect morphological features: round shape, heterogeneity and/or irregular borders (classified as doubtful cN+).
  • Staging rectal MRI confirms absence of tumour deposits.
  • Staging rectal MRI confirms absence of extramural vascular invasion (EMVI).

Exclusion criteria:

A patient who meets one or more of the following criteria will be excluded from participation in this study:

  • Lesions involving more than 50% of the circumference.
  • Total lesion size larger than 6 cm.
  • Prior endoscopic or surgical resection attempts of the tumour.
  • Recurrent cancer after previous surgical or endoscopic local resection.
  • Severe pre-existing faecal incontinence with impaired quality of life.
  • Inflammatory bowel disease (IBD) with previous inflammation of the rectum.
  • Previous pelvic irradiation or neoadjuvant therapy.
  • Poor general health that prevents the use of general anaesthesia.
  • Inability or contraindication to undergo MRI scan.
  • Concomitant malignancies or other severe medical conditions that, in the opinion of the multidisciplinary team (MDT), are likely to result in death within 5 years.
  • AJCC stage II, III or IV CRC within the last 5 years or synchronous CRC.
  • Inability to complete questionnaires or sign informed consent.
  • Known pregnancy.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Endoscopic intermuscular dissection (EID)

A participant randomly allocated to the EID arm will undergo an EID procedure at one of the participating study centres. Pre-procedural preparation and perioperative management will follow the standard-of-care protocols. The EID procedure will be performed according to the procedure definition and study protocol.

EID is an endoscopic local excision technique used for the resection of early-stage rectal tumours. The procedure uses a flexible endoscope to dissect between the inner (circular) and outer (longitudinal) muscles of the m. propria leaving the outer rectal wall layers intact. It is performed under conscious sedation by a gastroenterologist.

Active Comparator: Transanal minimally invasive surgery (TAMIS)

A participant randomly allocated to the TAMIS arm will undergo a TAMIS procedure at one of the participating study centres. Participants will be prepared according to the standard-of-care protocol. TAMIS will be performed as a full-thickness approach according to the procedure protocol; however, for lesions located in areas with limited or absent mesorectal fat, a full-thickness excision should be avoided. In these cases, an intermuscular approach may be adopted. The planned dissection plane (full-thickness or intermuscular) will be determined by the study steering committee based on preoperative radiographic and endoscopic assessment.

TAMIS is a minimally invasive transanal surgical technique used for the local excision of early-stage rectal tumours. A transanal platform is inserted into the anus to allow access with laparoscopic instruments. The procedure may be performed using a full-thickness or an intermuscular approach, based on tumour characteristics and surgical planning. The procedure is performed under general anesthesia by surgeons.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Rate of complete R0 resection between TAMIS and EID procedures
Time Frame: Assessed immediately after local excision procedure

The rate of complete R0 resection, defined as complete en-bloc resection with cancer free resection margins of >0.1mm, will be evaluated.

Assessed immediately after local excision procedure

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Incidence of procedure-related adverse events
Time Frame: Procedure-related adverse events will be recorded for 30 days post-procedure.

Procedure-related adverse events will be registered and recorded according to standard clinical practice in the Dutch Registration of Complications of Endoscopy (DRCE) or Dutch Surgical Colorectal Audit (DSCA). Details of all procedure-related complications within 30 days will be recorded in the eCRF and entered in ALEA database.

Procedure-related adverse events will be recorded for 30 days post-procedure.
Postprocedural pain scores
Time Frame: VAS scores will be recorded for 30 days post-procedure

Post-procedural recovery and pain will be assessed using a pain diary for the first 30 days following the procedure. Participants will record their daily pain intensity using a visual analogue scale (VAS), as well as their use of analgesic medication, until they report no pain for two consecutive days.

VAS scores will be recorded for 30 days post-procedure
Recovery scores
Time Frame: Assessed 30 days post-procedure

Post-procedural recovery will be assessed for the first 30 days following the procedure. Level of recovery, defined as the participant's ability to perform activities of daily living, will be recorded at on days 1, 3, 7, 14, and 30 post-procedure.

Assessed 30 days post-procedure
Rate of curative local excisions for pT1sm2-3 rectal cancer
Time Frame: Assessed immediately after local excision procedure

The rate of curative local excisions for pT1sm2-3 rectal cancer will be recorded. A curative local excision refers to pT1sm2-3 lesions with a complete R0 resection and the absence of additional histological risk factors.

Assessed immediately after local excision procedure
Dissection plane evaluation
Time Frame: Assessed immediately after local excision procedure

The rate of concordance between the definitive dissection plane and initially intended dissection plane prior to local excision (e.g., presence of longitudinal m. propria following an intended intermuscular dissection) will be evaluated. Only CRC pathologists trained within the PATCH study will assess the EID and TAMIS specimens to minimize interobserver variability.

Assessed immediately after local excision procedure
Quality of local excision specimen
Time Frame: Assessed immediately after local excision procedure

The quality of local excision specimens will be reviewed by a CRC pathologist for segment fragmentation, margin assessment, and the presence of muscularis propria underneath the invasive front (circular/longitudinal). Histological handling and evaluation of the resection specimen will be performed at participating centers according to standard care procedures. Only CRC pathologists trained within the PATCH study will handle EID and TAMIS specimens to minimize interobserver variability.

Assessed immediately after local excision procedure
Postoperative adverse events
Time Frame: Assessed for the first 30 days post-operatively

In the event that a total mesorectal excision (TME) is performed after local excision, post-operative adverse events (Clavien-Dindo classification) will be assessed for the first 30 days following TME.

Assessed for the first 30 days post-operatively
TME specimen quality after EID vs TAMIS
Time Frame: Assessed immediately after TME

In the event that a total mesorectal excision (TME) is performed after local excision, the quality of completion surgery will be systematically assessed. This includes TME specimen quality (Quirke classification).

Assessed immediately after TME
Circumferential resection margin status following completion surgery
Time Frame: Assessed immediately after TME

In the event that a total mesorectal excision (TME) is performed after local excision, the quality of completion surgery will be systematically assessed. This includes circumferential resection margin status.

Assessed immediately after TME
Conversion rate to laparotomy
Time Frame: Assessed immediately after TME

In the event that a total mesorectal excision (TME) is performed after local excision, the quality of completion surgery will be systematically assessed. This includes conversion rate to laparotomy.

Assessed immediately after TME
Rate of non-restorative TME procedures
Time Frame: Assessed immediately after TME

In the event that a total mesorectal excision (TME) is performed after local excision, the quality of completion surgery will be systematically assessed. This includes rate of non-restorative procedures.

Assessed immediately after TME
Functional Outcomes
Time Frame: Functional outcomes will be measured via LARS scores within a period of 12 months.

Functional outcomes will be measured using the validated Low Anterior Resection Syndrome (LARS) score at baseline, 1, 3, 6, and 12 months. The LARS score is 5-question survey tool used to measure bowel dysfunction after rectal cancer surgery. Total points range from 0 to 42, in which a higher scores indicate more severe symptoms and poor bowel functionality.

Functional outcomes will be measured via LARS scores within a period of 12 months.
Health related quality of life (QLQ-C30)
Time Frame: Questionnaires will be completed within a period of 3 years.

Health related Quality of Life (QoL) will be assessed using the validated Quality of Life Questionnaire - Core 30 (QLQ-C30) surveys. The QLQ-C30 contains 30 questions that measure the health-related quality of life of cancer patients. All of the scales and single-items range from 0 to 100. A higher score for the functioning scales and global health status implies a better level of functioning. Higher scores on the symptom and single-item scales indicate a higher level of symptoms. Questionnaires will be sent at baseline, 1, 3, 12, and 36 months. All questionnaires will be sent at predefined intervals electronically or collected on paper forms.

Questionnaires will be completed within a period of 3 years.
Health related quality of life (QLQ-CR29)
Time Frame: Surveys will be completed within a period of 3 years.

Health related Quality of Life (QoL) will be assessed using the validated Quality of Life Questionnaire - Colorectal Research 29 (QLQ-CR29). This survey contains 29 questions regarding burden of symptoms, side effects, body image, and sexual functioning. Scores scale from 0-100 with higher scores on symptom scales indicating a higher symptom burden, while higher scores on functional scales indicate better functionality. Questionnaires will be sent at baseline, 1, 3, 12, and 36 months. All questionnaires will be sent at predefined intervals electronically or collected on paper forms.

Surveys will be completed within a period of 3 years.
Health related quality of life (EQ-5D-5L)
Time Frame: Surveys will be completed within a period of 3 years.

Health-related quality of life (QoL) will be assessed using the validated EuroQol 5-Dimension 5-Level questionnaire (EQ-5D-5L). The EQ-5D-5L assesses health across five dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Each dimension is rated on a five-level scale from 1 (no problems) to 5 (extreme problems), with higher scores indicating greater impairment in the respective health dimension.

The EQ-5D-5L will be completed at baseline and at 1, 3, 12, and 36 months post-procedure. Questionnaires will be completed electronically or, where necessary, using paper forms.

Surveys will be completed within a period of 3 years.
Rectal preservation and stoma free survival
Time Frame: Following completion of procedure to end of follow-up at 3 years

The use of stoma and rates of rectal preservation will be measured within a 3 year period.

Following completion of procedure to end of follow-up at 3 years
Cancer recurrence rates
Time Frame: Cancer recurrences will be measured over a 3 year follow-up period

Intramural, locoregional, and distant 3-year cancer recurrence rates will be measured.

Cancer recurrences will be measured over a 3 year follow-up period
Survival Rates
Time Frame: Survival will be measured within the 3 year follow-up period.

Three-year disease-specific and overall survival will be measured within the 3 year follow-up period.

Survival will be measured within the 3 year follow-up period.
Healthcare costs
Time Frame: Healthcare costs will be measured from the time of enrollment to the end of the follow-up period at 3 years.

Healthcare costs will be measured using the validated iMCQ and iPCQ questionnaires at 1, 3, 12 and 36 months.

Healthcare costs will be measured from the time of enrollment to the end of the follow-up period at 3 years.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Barbara Bastiaansen, MD, Amsterdam University Medical Center

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

September 1, 2026

Primary Completion (Estimated)

March 1, 2029

Study Completion (Estimated)

September 1, 2032

Study Registration Dates

First Submitted

August 13, 2026

First Submitted That Met QC Criteria

September 22, 2026

First Posted (Actual)

September 29, 2026

Study Record Updates

Last Update Posted (Actual)

September 29, 2026

Last Update Submitted That Met QC Criteria

September 22, 2026

Last Verified

September 1, 2026

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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