An interventional study of Endoscopic Intermuscular Dissection (EID) and Transanal Minimally Invasive Surgery (TAMIS) in Rectal Cancer Stage I, sponsored by Amsterdam UMC, location VUmc. Not yet recruiting at 19 sites in Netherlands. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-29.
Sponsored by Amsterdam UMC, location VUmc · Not applicable, Interventional, and Treatment
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:
Participants will:
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.
To be eligible to participate in this study, a patient must meet all of the following criteria:
Exclusion criteria:
A patient who meets one or more of the following criteria will be excluded from participation in this study:
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.
Procedure: Endoscopic Intermuscular Dissection (EID)
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.
Procedure: Transanal Minimally Invasive Surgery (TAMIS)
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.
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.
Rate of complete R0 resection between TAMIS and EID procedures
The rate of complete R0 resection, defined as complete en-bloc resection with cancer free resection margins of \>0.1mm, will be evaluated.
Time frame: Assessed immediately after local excision procedure
Incidence of procedure-related adverse events
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.
Time frame: Procedure-related adverse events will be recorded for 30 days post-procedure.
Postprocedural pain scores
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.
Time frame: VAS scores will be recorded for 30 days post-procedure
Recovery scores
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.
Time frame: Assessed 30 days post-procedure
Rate of curative local excisions for pT1sm2-3 rectal cancer
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.
Time frame: Assessed immediately after local excision procedure
Dissection plane evaluation
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.
Time frame: Assessed immediately after local excision procedure
Quality of local excision specimen
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.
Time frame: Assessed immediately after local excision procedure
Postoperative adverse events
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.
Time frame: Assessed for the first 30 days post-operatively
TME specimen quality after EID vs TAMIS
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).
Time frame: Assessed immediately after TME
Circumferential resection margin status following completion surgery
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.
Time frame: Assessed immediately after TME
Conversion rate to laparotomy
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.
Time frame: Assessed immediately after TME
Rate of non-restorative TME procedures
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.
Time frame: Assessed immediately after TME
Functional Outcomes
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.
Time frame: Functional outcomes will be measured via LARS scores within a period of 12 months.
Health related quality of life (QLQ-C30)
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.
Time frame: Questionnaires will be completed within a period of 3 years.
Health related quality of life (QLQ-CR29)
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.
Time frame: Surveys will be completed within a period of 3 years.
Health related quality of life (EQ-5D-5L)
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.
Time frame: Surveys will be completed within a period of 3 years.
Rectal preservation and stoma free survival
The use of stoma and rates of rectal preservation will be measured within a 3 year period.
Time frame: Following completion of procedure to end of follow-up at 3 years
Cancer recurrence rates
Intramural, locoregional, and distant 3-year cancer recurrence rates will be measured.
Time frame: Cancer recurrences will be measured over a 3 year follow-up period
Survival Rates
Three-year disease-specific and overall survival will be measured within the 3 year follow-up period.
Time frame: Survival will be measured within the 3 year follow-up period.
Healthcare costs
Healthcare costs will be measured using the validated iMCQ and iPCQ questionnaires at 1, 3, 12 and 36 months.
Time frame: Healthcare costs will be measured from the time of enrollment to the end of the follow-up period at 3 years.
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Amsterdam UMC, location VUmc