MSH6 and PMS2 expression in colorectal carcinoma

Area of Science:

• Oncology
• Molecular Pathology
• Gastroenterology

Background:

• Microsatellite instability (MSI) is a significant biomarker in colorectal carcinomas (CRCs).
• The diagnostic and prognostic roles of immunohistochemical markers MSH6 and PMS2 for MSI in CRCs require further investigation.
• Understanding MSI status is vital for tailoring CRC treatment strategies.

Purpose of the Study:

• To evaluate the utility of MSH6 and PMS2 immunohistochemistry for detecting MSI in colorectal cancer.
• To correlate MSI status with clinicopathological features of CRCs.
• To explore the potential of MSI detection for improving CRC diagnosis and prognosis.

Main Methods:

• Analysis of 50 histologically confirmed colorectal carcinoma samples.
• Immunohistochemical staining for MSH6 and PMS2 protein expression.
• Correlation of MSI status (MSI-H) with tumor differentiation, stage, and lymph node involvement.

Main Results:

• Combined loss of MSH6 and PMS2 (MSI-H) was observed in 30% of the analyzed CRC cases.
• MSI-H was significantly associated with poorly differentiated tumors, T3 stage, stage II and III disease, and node-positive status.
• These findings highlight specific CRC subtypes with a higher prevalence of MSI.

Conclusions:

• MSH6 and PMS2 immunohistochemistry is an effective method for identifying MSI in colorectal cancer.
• MSI-H, indicated by MSH6/PMS2 loss, is linked to aggressive clinicopathological features in CRCs.
• This approach can enhance diagnostic accuracy and prognostic stratification for colorectal cancer patients.