MSI (Microsatellite Instaility) Testing

Colon cancer is one of the most common cancers in Korea and can be classified into MSI-H, MSI-L and MSS according to MSI testing and 90% of HNPCC (Hereditary nonpolyposis colorectal cancer) is found to be positive for Microsatellite Instability (MSI). Testing for microsatellite instability helps doctors determine whether a person is likely to have HNPCC and also helps doctors predict a person¡¯s prognosis, since MSI tumors tend to be less invasive than other types and have shown good survival rates in several reports.


Microsatellite markers

MSI testing can be performed using five recommended microsatellite markers. (BAT25, BAT26; D2S123,D5S346 and D17S250)


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PetaGen¡¯s MSI testing

PetaGen¡¯s MSI testing is fast, simple and requires no radio-isotope.
We provide fast results by an automated system which can perform analyses even in case of a minimum specimen.

Specimen preparation
Either formalin-fixed/paraffin-embedded or fresh frozen tissue samples of the tumor and matched normal tissue can be used . Also each DNA from the tumor and matched normal tissue are available.
Figure 1

A. Normal tissue of cancer patient
B. Tumor tissue of cancer patient
C. The overlapping diagram of both A and B

High Microsatellite instability (MSI-H)
A tumor is considered ¡°MSH-H¡± if changes are found in two or more regions.
Figure 2

A. Normal tissue of cancer patient
B. Tumor tissue of cancer patient
C. The overlapping diagram of both A and B

Microsatellite stability (MSS)
A tumor is considered ¡° MSS¡± if no changes are found between the patient¡¯s tumor tissue and normal tissue.