Colon CancerNCT07701408
ctDNA and TEP Levels in Colon Cancer
A study testing Additional Peripheral Venous Blood Sampling for ctDNA and TEP Biomarker Analysis in people with Colon Cancer, run by Institute of Oncology Ljubljana at 1 site in Slovenia.
Trial summary
This interventional cohort study will evaluate circulating tumor DNA (ctDNA) and tumor-educated platelets (TEP) as blood-based biomarkers in adults with stage III colon cancer who are planned to receive neoadjuvant systemic therapy followed by surgical resection. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Colon Cancer
- What is being tested?
- Additional Peripheral Venous Blood Sampling for ctDNA and TEP Biomarker Analysis
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 80 participants
- Where
- 1 siteSlovenia
- Study dates
- Nov 2026to Jun 2028
- 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 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age 18 years or older at the time of enrollment.
- Histologically confirmed adenocarcinoma of the colon.
- Stage III colon cancer, defined according to the applicable TNM classification based on clinical and imaging assessment.
- Confirmed mismatch repair (MMR) status, determined by immunohistochemistry and/or molecular methods.
- Planned neoadjuvant systemic therapy according to MMR status, followed by surgical resection with curative intent.
- ECOG performance status 0-2.
- Ability to understand the study and provide written informed consent.
Who cannot join
- Stage I, II, or IV colon cancer.
- Concurrent active malignant disease, except adequately treated non-melanoma skin cancer or carcinoma in situ.
- Severe comorbidities or medical conditions that prevent or substantially limit neoadjuvant systemic therapy or surgical resection.
- Known autoimmune disease requiring active immunosuppressive treatment in patients with dMMR tumors.
- Pregnancy or breastfeeding.
- Inability or unwillingness to provide written informed consent.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Slovenia1 site
Institute of Oncology Ljubljana
Ljubljana, 1000
Tanja Mesti, MD, +386 1 5879 287, tmesti@onko-i.si
Klavdija Korošec, +38631630065, kkorosec@onko-i.si
About this study
Official title: Determination of ctDNA and TEP Levels in Patients With Colon Cancer Receiving Neoadjuvant Systemic Therapy
This interventional cohort study will evaluate circulating tumor DNA (ctDNA) and tumor-educated platelets (TEP) as blood-based biomarkers in adults with stage III colon cancer who are planned to receive neoadjuvant systemic therapy followed by surgical resection.
Treatment will be given according to routine clinical practice and will depend on the biological characteristics of the tumor, including mismatch repair status. Participants will provide additional blood samples at predefined time points before, during, and after treatment and surgery. These samples will be used to analyze ctDNA and TEP and to assess whether changes in these biomarkers are associated with radiological response, pathological response, and disease-free outcomes.
Approximately 80 participants will be enrolled at the Institute of Oncology Ljubljana. Participants will not receive experimental drugs as part of this study.
Read the detailed description
This is a prospective interventional longitudinal cohort study of adult patients with histologically confirmed stage III colon adenocarcinoma who are planned to receive neoadjuvant systemic therapy followed by surgical resection with curative intent.
The study will evaluate the dynamics of circulating tumor DNA (ctDNA) and tumor-educated platelets (TEP) during neoadjuvant treatment and follow-up. Neoadjuvant systemic therapy will be selected according to routine clinical practice and tumor biology, including mismatch repair status. Patients with pMMR tumors may receive chemotherapy, while patients with dMMR tumors may receive immunotherapy, according to standard clinical decision-making.
The research intervention consists of additional peripheral venous blood sampling at predefined time points before treatment, during systemic treatment, before surgery, and after surgery. Blood samples will be analyzed for ctDNA and TEP-based biomarkers. Clinical, radiological, pathological, and follow-up data will be collected from routine medical documentation.
The primary objective is to determine whether the presence of ctDNA after completion of neoadjuvant systemic therapy is associated with pathological tumor response, defined as major pathological response (MPR), in patients with stage III colon cancer. Secondary and exploratory objectives include evaluation of the association between ctDNA, TEP profiles, radiological response, recurrence-free outcomes, and disease-free outcomes.
Approximately 80 participants will be enrolled. The study is academic and non-commercial. Participants will not receive experimental drugs as part of this study, and all therapeutic and diagnostic procedures will follow established clinical practice.
- Conditions
- Colon Cancer
- Being tested
- Additional Peripheral Venous Blood Sampling for ctDNA and TEP Biomarker Analysis
- Keywords
- ctDNA, Circulating Tumor DNA, Tumor-Educated Platelets, TEP, Neoadjuvant Systemic Therapy
- Medical subject headings
- Colonic Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Additional Peripheral Venous Blood Sampling for ctDNA and TEP Biomarker AnalysisProcedure or surgery
Additional peripheral venous blood samples will be collected at predefined time points before treatment, during systemic treatment, before surgery, and after surgery. Samples will be analyzed for circulating tumor DNA (ctDNA) and tumor-educated platelets (TEP).
| Study group | Role | What they receive |
|---|---|---|
| Biomarker Assessment Cohort | Other | Participants with stage III colon cancer receiving neoadjuvant systemic therapy according to routine clinical practice will undergo additional peripheral venous blood sampling at predefined time points for ctDNA and TEP biomarker analysis. Receives: Procedure: Additional Peripheral Venous Blood Sampling for ctDNA and TEP Biomarker Analysis |
What is being measured
The primary outcome is the main question the study is designed to answer.
Percentage of Participants With Major Pathological Response in the Post-Neoadjuvant ctDNA Assessment
Major pathological response will be assessed by histopathological evaluation of the surgical resection specimen after completion of neoadjuvant systemic therapy. The unit of measure will be the percentage of participants with major pathological response. ctDNA status after completion of neoadjuvant systemic therapy will be used as a pre-specified stratification variable in the statistical analysis.
Measured: From completion of neoadjuvant systemic therapy to pathological assessment after surgical resection, approximately 3 to 6 months.
Secondary outcomes (6)
Percentage of Participants With Objective Radiological Response According to RECIST 1.1
Radiological response will be assessed according to RECIST version 1.1 using routine preoperative imaging. Objective radiological response will include complete response and partial response. The unit of measure will be the percentage of participants with objective radiological response. ctDNA status after completion of neoadjuvant therapy will be used as a pre-specified stratification variable in the statistical analysis.
Measured: From baseline to preoperative radiological assessment, approximately 3 to 6 months.
Percentage of Participants Alive and Disease-Free at 12 Months After Surgical Resection
Disease-free status will be assessed using routine clinical, radiological, and follow-up documentation. The outcome will be defined as being alive and without disease recurrence at 12 months after surgical resection. The unit of measure will be the percentage of participants alive and disease-free at 12 months. ctDNA status after completion of neoadjuvant therapy will be used as a pre-specified stratification variable in the statistical analysis.
Measured: 12 months after surgical resection.
Percentage of Participants With Early Disease Recurrence Within 12 Months After Surgical Resection in the Postoperative ctDNA Assessment
Early disease recurrence will be assessed using routine clinical, radiological, and follow-up documentation. The unit of measure will be the percentage of participants with disease recurrence within 12 months after surgical resection. Postoperative ctDNA status will be used as a pre-specified stratification variable in the statistical analysis.
Measured: Up to 12 months after surgical resection.
Percentage of Participants With Early Disease Recurrence Within 12 Months After Surgical Resection in the Postoperative TEP Assessment
Early disease recurrence will be assessed using routine clinical, radiological, and follow-up documentation. The unit of measure will be the percentage of participants with disease recurrence within 12 months after surgical resection. Postoperative tumor-educated platelet status will be used as a pre-specified stratification variable in the statistical analysis.
Measured: Up to 12 months after surgical resection.
Percentage of Participants With Major Pathological Response in the Baseline ctDNA Assessment
Major pathological response will be assessed by histopathological evaluation of the surgical resection specimen. The unit of measure will be the percentage of participants with major pathological response. Baseline ctDNA status will be used as a pre-specified stratification variable in the statistical analysis.
Measured: From baseline to pathological assessment after surgical resection, approximately 3 to 6 months.
Percentage of Participants With Pathological Complete Response After Surgical Resection
Pathological complete response will be assessed by histopathological evaluation of the surgical resection specimen. The unit of measure will be the percentage of participants with pathological complete response. Baseline ctDNA status will be used as a pre-specified stratification variable in the statistical analysis.
Measured: From baseline to pathological assessment after surgical resection, approximately 3 to 6 months.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted14 Jul 2026
- Study startNov 2026 (estimated)
- Primary completionJun 2028 (estimated)
- Study completionJun 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Colon CancerStudies 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
- Diagnosis
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- All participants will undergo additional peripheral venous blood sampling at predefined time points for ctDNA and TEP biomarker analysis while receiving neoadjuvant systemic therapy according to routine clinical practice.
- Masking
- None (open label)
- Enrolment
- 80 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Institute of Oncology Ljubljana
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07701408
- Sponsor's protocol ID
- ORI2026-25
- Status last verified
- Oct 2026
- First submitted
- 18 Jun 2026
- Last updated
- 7 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 7 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Determination of ctDNA and TEP Levels in Patients With Colon Cancer Receiving Neoadjuvant Systemic Therapy
- ClinicalTrials.gov ID
- NCT07701408
- Acronym / sponsor ID
- ORI2026-25
- Conditions
- Colon Cancer
- Keywords
- ctDNA, Circulating Tumor DNA, Tumor-Educated Platelets, TEP, Neoadjuvant Systemic Therapy
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 80 participants (estimated)
- Lead sponsor
- Institute of Oncology LjubljanaUniversity, hospital or other
- Study start
- Nov 2026 (estimated)
- Primary completion
- Jun 2028 (estimated)
- Study completion
- Jun 2028 (estimated)
- First posted
- 14 Jul 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.
This interventional cohort study will evaluate circulating tumor DNA (ctDNA) and tumor-educated platelets (TEP) as blood-based biomarkers in adults with stage III colon cancer who are planned to receive neoadjuvant systemic therapy followed by surgical resection.
Treatment will be given according to routine clinical practice and will depend on the biological characteristics of the tumor, including mismatch repair status. Participants will provide additional blood samples at predefined time points before, during, and after treatment and surgery. These samples will be used to analyze ctDNA and TEP and to assess whether changes in these biomarkers are associated with radiological response, pathological response, and disease-free outcomes.
Approximately 80 participants will be enrolled at the Institute of Oncology Ljubljana. Participants will not receive experimental drugs as part of this study.
Detailed description
This is a prospective interventional longitudinal cohort study of adult patients with histologically confirmed stage III colon adenocarcinoma who are planned to receive neoadjuvant systemic therapy followed by surgical resection with curative intent.
The study will evaluate the dynamics of circulating tumor DNA (ctDNA) and tumor-educated platelets (TEP) during neoadjuvant treatment and follow-up. Neoadjuvant systemic therapy will be selected according to routine clinical practice and tumor biology, including mismatch repair status. Patients with pMMR tumors may receive chemotherapy, while patients with dMMR tumors may receive immunotherapy, according to standard clinical decision-making.
The research intervention consists of additional peripheral venous blood sampling at predefined time points before treatment, during systemic treatment, before surgery, and after surgery. Blood samples will be analyzed for ctDNA and TEP-based biomarkers. Clinical, radiological, pathological, and follow-up data will be collected from routine medical documentation.
The primary objective is to determine whether the presence of ctDNA after completion of neoadjuvant systemic therapy is associated with pathological tumor response, defined as major pathological response (MPR), in patients with stage III colon cancer. Secondary and exploratory objectives include evaluation of the association between ctDNA, TEP profiles, radiological response, recurrence-free outcomes, and disease-free outcomes.
Approximately 80 participants will be enrolled. The study is academic and non-commercial. Participants will not receive experimental drugs as part of this study, and all therapeutic and diagnostic procedures will follow established clinical practice.
Study design
- Primary purpose
- Diagnosis
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- All participants will undergo additional peripheral venous blood sampling at predefined time points for ctDNA and TEP biomarker analysis while receiving neoadjuvant systemic therapy according to routine clinical practice.
| Arm | Type | Receives |
|---|---|---|
| Biomarker Assessment Cohort | Other | Procedure: Additional Peripheral Venous Blood Sampling for ctDNA and TEP Biomarker AnalysisParticipants with stage III colon cancer receiving neoadjuvant systemic therapy according to routine clinical practice will undergo additional peripheral venous blood sampling at predefined time points for ctDNA and TEP biomarker analysis. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (7 listed)
- Age 18 years or older at the time of enrollment.
- Histologically confirmed adenocarcinoma of the colon.
- Stage III colon cancer, defined according to the applicable TNM classification based on clinical and imaging assessment.
- Confirmed mismatch repair (MMR) status, determined by immunohistochemistry and/or molecular methods.
- Planned neoadjuvant systemic therapy according to MMR status, followed by surgical resection with curative intent.
Key exclusion criteria (6 listed)
- Stage I, II, or IV colon cancer.
- Concurrent active malignant disease, except adequately treated non-melanoma skin cancer or carcinoma in situ.
- Severe comorbidities or medical conditions that prevent or substantially limit neoadjuvant systemic therapy or surgical resection.
- Known autoimmune disease requiring active immunosuppressive treatment in patients with dMMR tumors.
- Pregnancy or breastfeeding.
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 |
|---|---|---|
| Additional Peripheral Venous Blood Sampling for ctDNA and TEP Biomarker AnalysisAdditional peripheral venous blood samples will be collected at predefined time points before treatment, during systemic treatment, before surgery, and after surgery. Samples will be analyzed for circulating tumor DNA (ctDNA) and tumor-educated platelets (TEP). | Procedure or surgery | Biomarker Assessment Cohort |
Primary outcome
Percentage of Participants With Major Pathological Response in the Post-Neoadjuvant ctDNA Assessment
Time frame: From completion of neoadjuvant systemic therapy to pathological assessment after surgical resection, approximately 3 to 6 months.
Major pathological response will be assessed by histopathological evaluation of the surgical resection specimen after completion of neoadjuvant systemic therapy. The unit of measure will be the percentage of participants with major pathological response. ctDNA status after completion of neoadjuvant systemic therapy will be used as a pre-specified stratification variable in the statistical analysis.
6 secondary outcomes
Percentage of Participants With Objective Radiological Response According to RECIST 1.1
Time frame: From baseline to preoperative radiological assessment, approximately 3 to 6 months.
Percentage of Participants Alive and Disease-Free at 12 Months After Surgical Resection
Time frame: 12 months after surgical resection.
Percentage of Participants With Early Disease Recurrence Within 12 Months After Surgical Resection in the Postoperative ctDNA Assessment
Time frame: Up to 12 months after surgical resection.
Percentage of Participants With Early Disease Recurrence Within 12 Months After Surgical Resection in the Postoperative TEP Assessment
Time frame: Up to 12 months after surgical resection.
Percentage of Participants With Major Pathological Response in the Baseline ctDNA Assessment
Time frame: From baseline to pathological assessment after surgical resection, approximately 3 to 6 months.
Percentage of Participants With Pathological Complete Response After Surgical Resection
Time frame: From baseline to pathological assessment after surgical resection, approximately 3 to 6 months.
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 7 Oct 2026.
- Individual participant dataSharing planned: No
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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.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Additional Peripheral Venous Blood Sampling for ctDNA and TEP Biomarker Analysis in people with Colon Cancer, run by Institute of Oncology Ljubljana at 1 site in Slovenia.
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 7 inclusion and 6 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: opening soon, as of the sponsor's last update on 7 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Slovenia. 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?
Contact Tanja Mesti, MD (+386 1 5879 287, tmesti@onko-i.si), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Percentage of Participants With Major Pathological Response in the Post-Neoadjuvant ctDNA Assessment (time frame: From completion of neoadjuvant systemic therapy to pathological assessment after surgical resection, approximately 3 to 6 months.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 7 Oct 2026.