Microsatellite instability in colorectal cancer

Area of Science:

• Oncology
• Molecular Biology
• Pathology

Background:

• Colorectal cancer (CRC) is a significant health concern.
• Microsatellite instability (MSI) is a key molecular feature in CRC.
• Understanding MSI's clinicopathological correlations is crucial for effective treatment strategies.

Purpose of the Study:

• To investigate the relationship between MSI and clinicopathological characteristics of CRC.
• To facilitate targeted therapy and immunotherapy for MSI-related CRC.
• To establish a basis for improved prognostic assessments in CRC patients.

Main Methods:

• Retrospective analysis of CRC patient data from January 2021 to September 2022.
• Collection of clinicopathological information including age, tumor size, and MSI status.
• Utilized Polymerase Chain Reaction (PCR) and Immunohistochemistry (IHC) to assess MSI and mismatch repair (MMR) protein expression.

Main Results:

• MSI-related CRC predominantly affects individuals over 50 years old.
• Tumor characteristics associated with MSI include diameter (5-10 cm), right colon location, and moderate to poor differentiation.
• High concordance (96.6%) was observed between PCR and IHC methods for MSI/MMR status determination.

Conclusions:

• MMR protein expression correlates with age, tumor diameter, location, and differentiation in CRC.
• No significant association was found between MMR expression and gender, lymphovascular invasion, perineural invasion, lymph node metastasis, TNM stage, or P53 expression.
• The high consistency between PCR and IHC validates their use in clinical practice for MSI assessment.