Clinical trial · Observational
Current Microsatellite Stability Results in Colon Cancer
TKRCD-MSI Study: Current Microsatellite Stability Findings in Colon Cancer - Nationwide Experience From Turkey
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Summary
Brief summary (as posted)
The goal of this prospective observational study is to learn more about how a specific type of DNA repair issue-called mismatch repair deficiency (dMMR)-affects colon cancer in people living in Turkey. The study will look at how often dMMR occurs, how it is reported, and how it relates to treatment outcomes. The main questions it aims to answer are: * How common is dMMR in colon cancer, and does it vary by where the tumor is in the colon? * How often is MSI (microsatellite instability) status reported in colon cancer biopsy reports before surgery? * How do different types of dMMR (such as MLH1/PMS2 loss, MSH2/MSH6 loss, or sporadic cases) affect survival over three years? Participants will: * Be people who had surgery for colon cancer between June 1, 2025 and May 31, 2026 at hospitals in Turkey that treat more than 30 colon cancer cases each year. * Have their medical and pathology data reviewed, including information about tumor location, biopsy results, surgery, and treatment. This study will not involve any new treatments. Instead, it will use existing medical records to better understand how to improve care and identify people who may benefit from immunotherapy. Results from this study will be shared at scientific meetings and published in medical journals.
Conditions
Conditions (3)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Colon Adenocarcinoma | Colon Adenocarcinoma | ONTOLOGY_EXACT | 0.98 |
| MSI Negative Colorectal Cancer | — | UNRESOLVED | — |
| MSI Positive Colorectal Cancer | — | UNRESOLVED | — |
Interventions
Interventions (0)
Data not yet available
Design
Arms and outcomes
Arms (3)
- label
- MLH1/PMS2 loss group
- description
- Participants whose tumors show loss of MLH1 and PMS2 protein expression, typically associated with dMMR or MLH1 promoter hypermethylation. These tumors will be analyzed for clinical features and oncologic outcomes (DFS and OS) over 3 years.
- label
- MSH2/MSH6 Loss Group
- description
- Participants whose tumors show loss of MSH2 and MSH6 protein expression. This pattern is commonly associated with Lynch syndrome, a hereditary form of mismatch repair deficiency. Prognostic and treatment outcome data will be analyzed.
- label
- Sporadic Group (pMMR)
- description
- Participants with no loss of MMR protein expression (proficient MMR; pMMR). These cases represent sporadic tumors without mismatch repair deficiency and will serve as a comparison group for evaluating oncologic outcomes.
Primary outcomes (1)
- measure
- Prevalence and Anatomical Distribution of dMMR in Colon Cancer in Turkey
- timeFrame
Eligibility
Eligibility (as posted)
- Sex
- All
- Minimum age
- 18 Years
Show eligibility criteria text
Inclusion Criteria: Patients who have undergone curative-intent surgery for colon adenocarcinoma between June 1, 2025, and May 31, 2026 Surgery performed at a center with \>30 colon cancer surgeries per year Availability of MMR protein immunohistochemistry (IHC) and/or MSI test results from resection specimen and/or preoperative endoscopic biopsy Signed informed consent for participation and data collection Exclusion Criteria: Non-adenocarcinoma malignancies of the colon (e.g., neuroendocrine tumors, lymphomas) Rectal cancers (defined as tumors within 15 cm of the anal verge on endoscopy or MRI) Incomplete medical or pathological records preventing classification of MMR status
References
Publications (2)
- BACKGROUNDde Gooyer PGM, Verschoor YL, van den Dungen LDW, Balduzzi S, Marsman HA, Geukes Foppen MH, Grootscholten C, Dokter S, den Hartog AG, Verbeek WHM, Woensdregt K, van den Broek JJ, Oosterling SJ, Schumacher TN, Kuhlmann KFD, Beets-Tan RGH, Haanen JBAG, van Leerdam ME, van den Berg JG, Chalabi M. Neoadjuvant nivolumab and relatlimab in locally advanced MMR-deficient colon cancer: a phase 2 trial. Nat Med. 2024 Nov;30(11):3284-3290. doi: 10.1038/s41591-024-03250-w. Epub 2024 Sep 15. PMID 39278994
- BACKGROUNDAnderson CE, Liska D. Treatment of Microsatellite-Unstable Rectal Cancer in Sporadic and Hereditary Settings. Clin Colon Rectal Surg. 2023 Aug 11;37(4):233-238. doi: 10.1055/s-0043-1770717. eCollection 2024 Jul. PMID 38882941