Rectal NeoplasmsMSTNCT07376980
The SMART Trial: Modified Single-Stapled Anastomosis in Laparoscopic or Robotic Low Anterior Resection for Rectal Cancer
A study testing Modified single-stapled anastomosis technique in people with Rectal Neoplasms and Rectal Neoplasms Malignant, run by Korea University Anam Hospital at 6 sites in South Korea.
Trial summary
The goal of this clinical trial is to learn whether a modified single-stapled anastomosis (MST) can reduce anastomotic leakage compared with the conventional double-stapled technique (DST) in adult patients undergoing laparoscopic or robotic low anterior resection for rectal cancer. Read more about this study
- Who is it for?
- Ages 19 years and older
- Conditions the study is for
- Rectal Neoplasms, Rectal Neoplasms Malignant, Rectal Cancer
- What is being tested?
- Modified single-stapled anastomosis technique
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 450 participants
- Where
- 6 sitesSouth Korea
- Study dates
- 20 Dec 2025to 30 Dec 2030
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 19 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Adult patients with rectal cancer who are scheduled to undergo laparoscopic or robotic low anterior resection
- histologically confirmed rectal adenocarcinoma located within 15cm from anal verge.
- ECOG performance status of 0 to 2
- Any clinical stage
Who cannot join
- Who have significant comorbidities or history of abdominal surgeries that would preclude a minimally invasive approach
- Bowel obstruction for perforation requiring emergency surgey
- Concurrent, or recent treatment for colorectal or other malignancies within the past five years
- Presence of inflammatory bowel diseases
- Hereditary colorectal cancer syndrome
Trial locations and contacts
6 sites in 1 country. Contact the study team or a site near you to ask about taking part.
6 sites in 1 country
South Korea6 sites
Kyungpook National University Chilgok Hospital
Daegu, Gyeongsangbuk-do, 41404
Kyung Hee University Hospital
Seoul, 02447
Korea University Anam Hospital
Seoul, 02841
Seoul National University Hospital
Seoul, 03080
Severance Hospital
Seoul, 03722
St. Vincent's Hospital
Suwon, Gyeonggi-do, 16247
About this study
Official title: Modified Single-Stapled Anastomosis in Laparoscopic or Robotic Low Anterior Resection for Rectal Cancer: The SMART Trial (Single-Modified Anastomosis for Rectal Cancer Surgery Technique), A Multicenter Randomized Controlled Study
The goal of this clinical trial is to learn whether a modified single-stapled anastomosis (MST) can reduce anastomotic leakage compared with the conventional double-stapled technique (DST) in adult patients undergoing laparoscopic or robotic low anterior resection for rectal cancer.
The main questions it aims to answer are:
Read more
- Does MST lower the incidence of anastomotic leakage after rectal cancer surgery?
- Does MST improve short-term surgical outcomes compared with DST?
Researchers will compare the MST group with the DST group to see if MST leads to fewer anastomotic leaks and safer postoperative recovery.
Participants will:
Receive either MST or DST during minimally invasive rectal cancer surgery Undergo routine postoperative CT scans within one month after surgery to check for symptomatic or asymptomatic anastomotic leakage Attend scheduled follow-up visits and standard postoperative assessments as part of routine rectal cancer care
Read the detailed description
Anastomotic leakage is one of the most serious complications after low anterior resection (LAR) for rectal cancer. This complication can lead to infection, reoperation, prolonged hospitalization, higher medical costs, and worse long-term oncologic outcomes. Although laparoscopic and robotic surgery have improved short-term recovery compared with open surgery, the risk of anastomotic leakage remains a major concern.
The most commonly used reconstruction method during minimally invasive LAR is the double-stapled technique (DST). In DST, the rectum is transected with a linear stapler and then reconnected with a circular stapler. This creates an intersection between two staple lines, a known weak point that may be prone to leakage due to structural and ischemic vulnerability.
The modified single-stapled technique (MST) eliminates this intersection. Before applying the circular stapler, the two ends of the linear staple line on the rectal stump are brought together using a simple suture. This results in a single, centered staple line that the circular stapler incorporates completely into the anastomosis. Early studies, including a previous randomized trial, suggest that MST significantly reduces anastomotic leakage compared with DST.
This multicenter randomized controlled trial aims to provide high-quality evidence on the effectiveness of MST in reducing anastomotic leakage in patients undergoing laparoscopic or robotic LAR for rectal cancer. A total of 440 adult patients will be enrolled across multiple high-volume university hospitals in South Korea. Participants will be randomly assigned in a 1:1 ratio to receive MST or DST. Randomization will be stratified by sex, neoadjuvant treatment, and study center.
To ensure consistent surgical quality, all participating colorectal surgeons will complete a pre-trial standardization workshop and submit unedited surgical videos for competency review. All surgical procedures will follow standardized steps, and perioperative care will be based on established Enhanced Recovery After Surgery (ERAS) protocols.
The primary outcome is the rate of anastomotic leakage within one month after surgery. All participants will undergo routine abdominopelvic CT scans within this time window to detect both symptomatic and asymptomatic leaks. Secondary outcomes include postoperative complications, operative time, distal resection margin length, hospital stay, and long-term oncologic outcomes such as recurrence and survival. If MST is shown to be superior to DST, this study may support a simple, low-cost, and easily adoptable modification to current surgical practice. MST does not require additional equipment or complex training, making it a potentially valuable technique that can improve patient safety and surgical outcomes in rectal cancer care across diverse clinical settings.
- Being tested
- Modified single-stapled anastomosis technique
- Keywords
- Rectal Cancer, Total Mesorectal Excision, Low Anterior Resection, Anastomotic Leak, Anastomosis, Surgical, Stapled anastomosis, Modified Single-Stapled Technique, Minimally Invasive Rectal Surgery
- Medical subject headings
- Rectal Neoplasms, Anastomotic Leak
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Modified single-stapled anastomosis techniqueProcedure or surgery
Also called Single-stapled anastomosis, Modified single-stapled anastomosis, Dog-ear-free anastomosis, Single-stapling technique
This intervention applies a modified single-stapled anastomosis specifically to low anterior resection (LAR), where the technique has not been previously evaluated in a randomized controlled trial. Although similar concepts have been explored in anterior resection, their application in LAR is technically more challenging due to the deeper pelvic working space and more limited access to the rectal stump. In earlier studies, approximation of the linear staple line was performed through a Pfannelstein incision or mini-laparotomy incision during specimen extraction. In contrast, this trial utilizes a fully intracorporeal approach.
| Study group | Role | What they receive |
|---|---|---|
| Modified single-stapled anastomosis technique | Experimental | Participants assigned to this arm will undergo minimally invasive low anterior resection using the modified single-stapled technique. After rectal resection, the two ends of the linear staple line of stump are approximated toward the center using a barbed suture. The circular stapler spike is introduced through the center of the staple line to ensure complete resection of the linear staple line, eliminating staple-line intersections. The reaminder of the procedure, including total mesorectal excision, follows standard oncologic principles. Receives: Procedure: Modified single-stapled anastomosis technique |
| Double-stapled anastomosis technique | No intervention | Participants assigned to this arm will undergo minimally invasive low anterior resection using the conventional double-stapled technique. The rectum is transected with linear stapler, followed by transanal introduction of a circular stapler to create an end-to-end anastomosis. The procedure represents current standard practice for low anterior resection in rectal cancer. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Anastomotic leakage
Anastomotic leakage will be assessed within 30 days after surgery using clinical evaluation and routine abdominopelvic computed tomography (APCT). Leakage is defined as any defect in the anastomosis that results in communication between the inside of the bowel and the surrounding tissue. Diagnostic criteria include clinical symptoms (such as fever, abdominal pain, or drainage contents), abnormal laboratory findings, or radiologic evidence of leakage on APCT. All leaks will be classified according to the grading system.
- Grade A: Leakage requiring no active therapeutic intervention.
- Grade B: Leakage requiring non-surgical management, such as antibiotics or percutaneous drainage.
- Grade C: Leakage requiring reoperation. Routine postoperative CT for all participants ensures consistent and standardized detection of both symptomatic and asymptomatic leaks.
Measured: within 30 days after surgery
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted29 Jan 2026
- Study start20 Dec 2025
- Primary completion30 Dec 2027 (estimated)
- Study completion30 Dec 2030 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Rectal NeoplasmsStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- This study uses a parallel assignment interventional model. Participants will be randomly allocated in a 1:1 ratio to one of two dependent surgical intervention arms: MST or DST. Each participatns will undergo only assigned surgical technique without crossover betwen groups.
- Masking
- Double blind
- Who is masked
- Participant, Outcomes assessor
- Enrolment
- 450 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Korea University Anam Hospital
- Sponsor type
- University, hospital or other
- Collaborators
- Kyunghee University Medical Center, Seoul National University Hospital, Kyungpook National University Chilgok Hospital, Saint Vincent's Hospital, Korea, Severance Hospital
- Responsible party
- Principal investigator, Kim, Jin, Korea University Anam Hospital
- Investigators
- Jin Kim, M.D., Ph.D, Principal investigator, Korea University Anam Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07376980
- Sponsor's protocol ID
- 2025AN0114
- Acronym
- MST
- Status last verified
- Jan 2026
- First submitted
- 3 Dec 2025
- Last updated
- 29 Jan 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: IPD will not be shared because the dataset contains sensitive clinical information, and secondary distribution is not permitted under the terms of institutional review board approvals and patient consent. Data access is restricted to the study investigators to protect participant privacy.
Publications
Ryu HS, Kwak JM, Baek SJ, Min BS, Cho MS, Yang SY, Park SJ, Park EJ, Park JS, Song SH, Kang SJ, Kye BH, Yoo N, Mun JY, Park JW, Kim MJ, Kim YJ, Kim J. Modified single-stapled anastomosis in laparoscopic or robotic low anterior resection for rectal cancer: protocol for a multicentre randomised controlled trial. BMJ Open. 2026 Sep 21;16(9):e120621. doi: 10.1136/bmjopen-2026-120621.
PubMed 42767745
Study at a glance
From the registry record, last updated by the sponsor on 29 Jan 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Modified Single-Stapled Anastomosis in Laparoscopic or Robotic Low Anterior Resection for Rectal Cancer: The SMART Trial (Single-Modified Anastomosis for Rectal Cancer Surgery Technique), A Multicenter Randomized Controlled Study
- ClinicalTrials.gov ID
- NCT07376980
- Acronym / sponsor ID
- MST / 2025AN0114
- Keywords
- Rectal Cancer, Total Mesorectal Excision, Low Anterior Resection, Anastomotic Leak, Anastomosis, Surgical, Stapled anastomosis, Modified Single-Stapled Technique, Minimally Invasive Rectal Surgery
- Study type
- Interventional
- Recruitment status
- Enrolling by invitation
- Enrolment
- 450 participants (estimated)
- Lead sponsor
- Korea University Anam HospitalUniversity, hospital or other
- Collaborators
- Kyunghee University Medical Center, Seoul National University Hospital, Kyungpook National University Chilgok Hospital, Saint Vincent's Hospital, Korea, Severance Hospital
- Study start
- 20 Dec 2025 (actual)
- Primary completion
- 30 Dec 2027 (estimated)
- Study completion
- 30 Dec 2030 (estimated)
- First posted
- 29 Jan 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this clinical trial is to learn whether a modified single-stapled anastomosis (MST) can reduce anastomotic leakage compared with the conventional double-stapled technique (DST) in adult patients undergoing laparoscopic or robotic low anterior resection for rectal cancer.
The main questions it aims to answer are:
- Does MST lower the incidence of anastomotic leakage after rectal cancer surgery?
- Does MST improve short-term surgical outcomes compared with DST?
Researchers will compare the MST group with the DST group to see if MST leads to fewer anastomotic leaks and safer postoperative recovery.
Participants will:
Receive either MST or DST during minimally invasive rectal cancer surgery Undergo routine postoperative CT scans within one month after surgery to check for symptomatic or asymptomatic anastomotic leakage Attend scheduled follow-up visits and standard postoperative assessments as part of routine rectal cancer care
Detailed description
Anastomotic leakage is one of the most serious complications after low anterior resection (LAR) for rectal cancer. This complication can lead to infection, reoperation, prolonged hospitalization, higher medical costs, and worse long-term oncologic outcomes. Although laparoscopic and robotic surgery have improved short-term recovery compared with open surgery, the risk of anastomotic leakage remains a major concern.
The most commonly used reconstruction method during minimally invasive LAR is the double-stapled technique (DST). In DST, the rectum is transected with a linear stapler and then reconnected with a circular stapler. This creates an intersection between two staple lines, a known weak point that may be prone to leakage due to structural and ischemic vulnerability.
The modified single-stapled technique (MST) eliminates this intersection. Before applying the circular stapler, the two ends of the linear staple line on the rectal stump are brought together using a simple suture. This results in a single, centered staple line that the circular stapler incorporates completely into the anastomosis. Early studies, including a previous randomized trial, suggest that MST significantly reduces anastomotic leakage compared with DST.
This multicenter randomized controlled trial aims to provide high-quality evidence on the effectiveness of MST in reducing anastomotic leakage in patients undergoing laparoscopic or robotic LAR for rectal cancer. A total of 440 adult patients will be enrolled across multiple high-volume university hospitals in South Korea. Participants will be randomly assigned in a 1:1 ratio to receive MST or DST. Randomization will be stratified by sex, neoadjuvant treatment, and study center.
To ensure consistent surgical quality, all participating colorectal surgeons will complete a pre-trial standardization workshop and submit unedited surgical videos for competency review. All surgical procedures will follow standardized steps, and perioperative care will be based on established Enhanced Recovery After Surgery (ERAS) protocols.
The primary outcome is the rate of anastomotic leakage within one month after surgery. All participants will undergo routine abdominopelvic CT scans within this time window to detect both symptomatic and asymptomatic leaks. Secondary outcomes include postoperative complications, operative time, distal resection margin length, hospital stay, and long-term oncologic outcomes such as recurrence and survival. If MST is shown to be superior to DST, this study may support a simple, low-cost, and easily adoptable modification to current surgical practice. MST does not require additional equipment or complex training, making it a potentially valuable technique that can improve patient safety and surgical outcomes in rectal cancer care across diverse clinical settings.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, outcomes assessor)
- Number of arms
- 2
- Model description
- This study uses a parallel assignment interventional model. Participants will be randomly allocated in a 1:1 ratio to one of two dependent surgical intervention arms: MST or DST. Each participatns will undergo only assigned surgical technique without crossover betwen groups.
| Arm | Type | Receives |
|---|---|---|
| Modified single-stapled anastomosis technique | Experimental | Procedure: Modified single-stapled anastomosis techniqueParticipants assigned to this arm will undergo minimally invasive low anterior resection using the modified single-stapled technique. After rectal resection, the two ends of the linear staple line of stump are approximated toward the center using a barbed suture. The circular stapler spike is introduced through the center of the staple line to ensure complete resection of the linear staple line, eliminating staple-line intersections. The reaminder of the procedure, including total mesorectal excision, follows standard oncologic principles. |
| Double-stapled anastomosis technique | No intervention | –Participants assigned to this arm will undergo minimally invasive low anterior resection using the conventional double-stapled technique. The rectum is transected with linear stapler, followed by transanal introduction of a circular stapler to create an end-to-end anastomosis. The procedure represents current standard practice for low anterior resection in rectal cancer. |
Who may qualify
- Ages
- 19 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Adult patients with rectal cancer who are scheduled to undergo laparoscopic or robotic low anterior resection
- histologically confirmed rectal adenocarcinoma located within 15cm from anal verge.
- ECOG performance status of 0 to 2
- Any clinical stage
Key exclusion criteria (5 listed)
- Who have significant comorbidities or history of abdominal surgeries that would preclude a minimally invasive approach
- Bowel obstruction for perforation requiring emergency surgey
- Concurrent, or recent treatment for colorectal or other malignancies within the past five years
- Presence of inflammatory bowel diseases
- Hereditary colorectal cancer syndrome
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Modified single-stapled anastomosis techniqueAlso: Single-stapled anastomosis, Modified single-stapled anastomosis, Dog-ear-free anastomosis, Single-stapling techniqueThis intervention applies a modified single-stapled anastomosis specifically to low anterior resection (LAR), where the technique has not been previously evaluated in a randomized controlled trial. Although similar concepts have been explored in anterior resection, their application in LAR is technically more challenging due to the deeper pelvic working space and more limited access to the rectal stump. In earlier studies, approximation of the linear staple line was performed through a Pfannelstein incision or mini-laparotomy incision during specimen extraction. In contrast, this trial utilizes a fully intracorporeal approach. | Procedure or surgery | Modified single-stapled anastomosis technique |
Primary outcome
Anastomotic leakage
Time frame: within 30 days after surgery
Anastomotic leakage will be assessed within 30 days after surgery using clinical evaluation and routine abdominopelvic computed tomography (APCT). Leakage is defined as any defect in the anastomosis that results in communication between the inside of the bowel and the surrounding tissue. Diagnostic criteria include clinical symptoms (such as fever, abdominal pain, or drainage contents), abnormal laboratory findings, or radiologic evidence of leakage on APCT. All leaks will be classified according to the grading system. * Grade A: Leakage requiring no active therapeutic intervention. * Grade B: Leakage requiring non-surgical management, such as antibiotics or percutaneous drainage. * Grade C: Leakage requiring reoperation. Routine postoperative CT for all participants ensures consistent and standardized detection of both symptomatic and asymptomatic leaks.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Jan 2026.
- Derived from this study: PubMed 42767745Ryu HS, Kwak JM, Baek SJ, Min BS, Cho MS, Yang SY, Park SJ, Park EJ, Park JS, Song SH, Kang SJ, Kye BH, Yoo N, Mun JY, Park JW, Kim MJ, Kim YJ, Kim J. Modified single-stapled anastomosis in laparoscopic or robotic low anterior resection for rectal cancer: protocol for a multicentre randomised controlled trial. BMJ Open. 2026 Sep 21;16(9):e120621. doi: 10.1136/bmjopen-2026-120621.
- Individual participant dataSharing planned: No. IPD will not be shared because the dataset contains sensitive clinical information, and secondary distribution is not permitted under the terms of institutional review board approvals and patient consent. Data access is restricted to the study investigators to protect participant privacy.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Jin Kim, M.D., Ph.D principal investigator
Korea University Anam Hospital
6 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Modified single-stapled anastomosis technique in people with Rectal Neoplasms and Rectal Neoplasms Malignant, run by Korea University Anam Hospital at 6 sites in South Korea.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: enrolling by invitation, as of the sponsor's last update on 29 Jan 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 6 sites in South Korea. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Anastomotic leakage (time frame: within 30 days after surgery). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07376980, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Jan 2026.