The mCRC Patients With pMMR/MSS or dMMR/MSI-H Status Received Palliative Chemotherapy Efficacy and Survival

Study Overview
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Brief Summary
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Deficient mismatch repair (dMMR) or microsatellite instability high (MSI-H) accounts for 4-5% in metastatic colorectal cancer (mCRC). The efficacy and survival of patients with dMMR/MSI-H status received palliative chemotherapy have not clear yet. In this study, the investigators observed the efficacy and survival of dMMR/MSI-H status mCRC patients received palliative first-line chemotherapy.

Detailed Description
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Colorectal cancer (CRC) is the one of most common cancer in the world. Loss of function of DNA mismatch repair (MMR) is an important mechanism of CRC development. Mutation or modification of MMR genes result in MMR protein deficient (dMMR) and microsatellite instability (MSI). It has been reported that the dMMR or MSI high (MSI-H) phenotype is present in approximately 15-18% of CRC patients. Most dMMR/MSI-H tumors are sporadic CRC, and only approximately 3% of dMMR/MSI-H tumors are Lynch syndrome (LS) or hereditary nonpolyposis colorectal carcinoma (HNPCC). The dMMR/MSI-H status was reported to be a predictive marker for adjuvant chemotherapy. Multiple retrospective studies showed that dMMR/MSI-H is correlated with a favorable prognosis in stage II/III CRC. Previous studies suggested that dMMR/MSI status may be a predictive marker of decreased benefit form adjuvant monotherapy of 5-fluorouracil (5-FU) in patients with stage II disease, but not in those with stage III disease. For metastatic colorectal cancer (mCRC), the relationship of the MMR/MSI phenotype and prognosis is unclear. Some researchers found that CRC patients with the dMMR/MSI-H phenotype have a worse prognosis. But other researchers thought the dMMR/MSI-H phenotype is no associate to efficacy and survival of palliative chemotherapy, even is benefit for efficacy and survival.Therefore, the aim of this study was to clarify whether the status of dMMR/MSI-H affected progression-free survival (PFS) in mCRC patients who received first-line palliative chemotherapy.

Official Title
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The Metastatic Colorectal Cancer Patients With Proficient Mismatch Repair (pMMR) / Microsatellite Stable (MSS) or Deficient Mismatch Repair (dMMR) / Microsatellite Instability High (MSI-H) Status Received Palliative Chemotherapy Efficacy and Survival

Conditions
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Colorectal Cancer Metastatic, Mismatch Repair Deficiency, Microsatellite Instability High

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 18 years old Histologically confirmed Metastatic colorectal adenocarcinoma; Immunohistochemistry confirmed mismatch repair status or polymerase chain reaction (pCR) / next-generation sequencing (NGS) confirmed microsatellite status Received palliative chemotherapy and have complete information of treatment Exclusion Criteria: Patients have not tested for mismatch repair or microsatellite Patients have not received palliative chemotherapy or received palliative chemotherapy but treatment information incomplete

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| pMMR/MSS mCRC patients<br>The metastatic colorectal cancer patients with proficient mismatch repair or microsatellite stable status. | |
| dMMR/MSI-H mCRC patients<br>The metastatic colorectal cancer patients with deficient mismatch repair or microsatellite instability high status. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Progression-Free Survival (PFS) | PFS as measured in accordance with the Response Evaluation Criteria In Solid Tumours (RECIST) version 1.1 | up to 24-36 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Response rate | Based on Response Evaluation Criteria in Solid Tumors 1.1 (RECIST 1.1) | From first patient first visit to 6 month after last patient first visit | 
| Disease Control Rate (DCR) | Based on Response Evaluation Criteria in Solid Tumors 1.1 (RECIST 1.1) | From first patient first visit to 6 month after last patient first visit | 
| Overall survival | The time from registration to death due to any cause, or censored at date last known alive. | up to approximately 9 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Colorectal Cancer Metastatic, Mismatch Repair Deficiency, Microsatellite Instability High, Chemotherapy