Microsatellite Instability in Colorectal Cancers

Study Overview
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Brief Summary
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In this study, we aimed to identify the different histopathological features of tumors with microsatellite instability (MSI) compared to microsatellite stable (MSS) in patients who underwent surgery for colorectal cancer. We also planned to determine how MSI affects prognostic parameters.

Detailed Description
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According to Global Cancer Statistics, higher than 1.9 million new cases of colorectal cancer (CRC) and 935,000 deaths are estimated to occur in 2020, representing about one in 10 cancer cases and deaths. Overall, it ranks third in colorectal incidence but second in mortality. In CRC evolution, the acquisition of genomic instability is a critical point, and there are at least two different pathways in the pathogenesis of CRC: the chromosomal instability (CIN) pathway (85%) and the microsatellite instability (MSI) pathway (15%). Microsatellite instability (MSI) is a phenotype that occurs due to a malfunction in the DNA repair mechanism and is seen in approximately 15% of colorectal cancers (CRCs). CRCs with MSI have different clinical features, such as a tendency to settle in the proximal colon, poor differentiation, and more lymphocytic infiltration in the tumor. It has been shown that CRCs with MSI have a better prognosis and respond differently to chemotherapy than CRCs with microsatellite stable (MSS). We aimed to evaluate the different histopathological features of tumors with MSI compared to MSS in patients who underwent surgery for colorectal cancer. We also planned to determine how MSI affects prognostic parameters such as mortality rate, recurrence, disease-free survival, cancer-specific survival, and overall survival.

Official Title
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Clinicopathological Outcomes of Microsatellite Instability in Colorectal Cancer

Conditions
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Colorectal Cancer, Colorectal Carcinoma, Microsatellite Instability High, Microsatellite Instability Low, Microsatellite Instability-High

Intervention / Treatment
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* Diagnostic Test: Microsatellite instability analysis


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Colorectal surgery patients Complete follow-up information Exclusion Criteria: Whose MSI status was not studied in the pathology material Missing follow-up information Colorectal resection for non-neoplastic diseases

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Microsatellite instability<br>Immunohistochemical analysis was performed for Microsatellite Instability (MSI) status of colorectal tumors tissue. | Diagnostic Test: Microsatellite instability analysis<br>* Molecular analysis for Microsatellite Instability (MSI) status was performed using immunohistochemistry (IHC). IHC now recognized as an approved method to highly precision predict MSI in colorectal cancer.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall Survival | Overall survival is defined as the time interval from the time of primary operation to the date of all-cause death or the last follow-up. | Five years | 
| Disease-Free Survival | Disease-Free Survival is defined as the time interval from the time of primary operation to disease recurrence or death. | Five years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Colorectal cancer, Prognostic factor, Microsatellite instability, Prognosis, Survival